2,2',3,3',4,4'-ヘキサクロロビフェニル

This compound is not very flammable but any fire involving this compound may produce dangerous vapors. You should evacuate the area. All firefighters should wear full-body protective clothing and use self-contained breathing apparatuses. You should extinguish any fires involving this chemical with a dry chemical, carbon dioxide, foam, or halon extinguisher. (NTP, 1992)

EYES: First check the victim for contact lenses and remove if present. Flush victim's eyes with water or normal saline solution for 20 to 30 minutes while simultaneously calling a hospital or poison control center. Do not put any ointments, oils, or medication in the victim's eyes without specific instructions from a physician. IMMEDIATELY transport the victim after flushing eyes to a hospital even if no symptoms (such as redness or irritation) develop.

Use dry chemical, carbon dioxide, or alcohol foam extinguishers. Vapors are heavier than air and will collect in low areas. Vapors in confined areas may explode when exposed to fire. Containers may explode in fire. Storage containers and parts of containers may rocket great distances, in many directions. If material or contaminated runoff enters waterways, notify downstream users of potentially contaminated waters. Notify local health and fire officials and pollution control agencies. From a secure, explosion-proof location, use water spray to cool exposed containers. If cooling streams are ineffective (venting sound increases in volume and pitch, tank discolors, or shows any signs of deforming), withdraw immediately to a secure position ... The only respirators recommended for fire fighting are self-contained breathing apparatuses that have full facepieces and are operated in a pressure-demand or other positive pressure mode. /Polychlorinated biphenyls/

If material on fire or involved in fire: Extinguish fire using agent suitable for type of surrounding fire. (Material itself does not burn or burns with difficulty.) Keep run-off water out of sewers and water sources. /Polychlorinated biphenyls/

Store in tightly closed containers in a cool, well-ventilated area away from strong oxidizers (such as chlorine, bromine, and fluorine). A regulated marked area should be established where this chemical is handled, used, or stored ... /Polychlorinated biphenyls/

Drums, transformers, and other containers should be frequently inspected for leakage. Store in a cool, dry, well-ventilated location. Detached storage must be used. /Polychlorinated biphenyls/

PCB material should be stored in closed containers, in ventilated areas. ... PCB's should be handled in isolated areas of the plant, where efficient ventilation systems remove airborne PCB's. ... /Polychlorinated biphenyls/

PRECAUTIONS FOR "CARCINOGENS": Storage site should be as close as practicable to lab in which carcinogens are to be used, so that only small quantities required for ... expt need to be carried. Carcinogens should be kept in only one section of cupboard, an explosion-proof refrigerator or freezer (depending on chemicophysical properties ...) that bears appropriate label. An inventory ... should be kept, showing quantity of carcinogen & date it was acquired ... Facilities for dispensing ... should be contiguous to storage area. /Chemical Carcinogens/

Evacuate and restrict persons not wearing protective equipment from area of spill or leak until cleanup is complete. Remove all ignition sources. Ventilate area of spill or leak. Absorb liquids in vermiculite, dry sand, earth, peat, carbon, or a similar material and deposit in sealed containers. Keep this chemical out of a confined space, such as a sewer, because of the possibility of an explosion, unless the sewer is designed to prevent the build-up of explosive concentrations. It may be necessary to contain and dispose of this chemical as a hazardous waste. If material or contaminated runoff enters waterways, notify downstream users of potentially contaminated waters. Contact your Department of Environmental Protection or your regional office of the federal EPA for specific recommendations ... Spills of one pound or more must be reported to the EPA. /Polychlorinated biphenyls/

Stop or control the leak, if this can be done without undue risk. Absorb in noncombustible material for proper disposal. /Polychlorinated biphenyls/

Environmental considerations: Land spill: Dig a pit, pond, lagoon, or holding area to contain liquid or solid material. /SRP: If time permits, pits, ponds, lagoons, soak holes, or holding areas should be sealed with an impermeable flexible membrane liner./ Dike surface flow using soil, sand bags, foamed polyurethane, or foamed concrete. Absorb bulk liquid with fly ash or cement powder, or commercial sorbents. /Polychlorinated biphenyls/

Environmental considerations: Water spill: Use natural barriers or oil spill control booms to limit spill travel. Remove trapped material with suction hoses. /Polychlorinated biphenyls/

For more Cleanup Methods (Complete) data for Aroclor 1260 (6 total), please visit the HSDB record page.

SMALL SPILLS AND LEAKAGE: If you should spill this chemical, use absorbent paper to pick up all liquid spill material. Your contaminated clothing and absorbent paper should be sealed in a vapor-tight plastic bag for eventual disposal. Solvent wash all contaminated surfaces with acetone followed by washing with a strong soap and water solution. Do not reenter the contaminated area until the Safety Officer (or other responsible person) has verified that the area has been properly cleaned.

SRP: The most favorable course of action is to use an alternative chemical product with less inherent propensity for occupational harm/injury/toxicity or environmental contamination. Recycle any unused portion of the material for its approved use or return it to the manufacturer or supplier. Ultimate disposal of the chemical must consider: the material's impact on air quality; potential migration in soil or water; effects on animal and plant life; and conformance with environmental and public health regulations.

Chemical treatment: Incineration (1650 °C) with scrubbing to remove any chlorine-containing products. In addition, some chemical waste landfills have been approved for PCB /polychlorinated biphenyls/ disposal. Treatment with metallic sodium has been advocated which yields a low molecular weight polyphenylene and sodium chloride. Recommendable methods: Incineration & landfill. Not recommendable methods: Open burning & use as a boiler fuel. Peer review: Incineration must be for more than 2 seconds at 1200 °C or higher for PCB waste. If PCB content of waste is less than 500 ppm any proper waste incinerator can be used as long as temp exceeds 800 °C for 0.5 sec. Combustion of PCB's can produce dioxins. Incineration at sea is a good method. (Peer-review conclusions of an IRPTC expert consultation (May 1985))

Experiments on the combustion of polychlorinated biphenyls (PCBs) in 1 m-long tube furnace indicated that PCBs containing approx 40% Cl is destroyed within 3-4 min at 900-1000 °C using 100% excess air. Temperatures greater than 1000 °C are required to destroy PCB scontaining approx 60% cl & distillation residues arising from PCB manufacturing. Domestic waste incinerators operating at 800-900 °C are unlikely to prove suitable for incinerating waste containing trace amounts of PCB. Pyrolysis experiments at 900 °C with nominal residence time of 3.5 sec gave 40-60% recovery of Cl as HCl from PCB. /Polychlorinated biphenyls/

Polychlorinated biphenyls (375 g) mixed in 1242 l of #2 fuel oil was disposed of in a cement kiln incinerator with a temperature range of 1400-1450 °C. The destruction efficiency was >99.9998%. /Polychlorinated biphenyls, from table/

For more Disposal Methods (Complete) data for Aroclor 1260 (12 total), please visit the HSDB record page.

SRP: The scientific literature for the use of contact lenses in industry is conflicting. The benefit or detrimental effects of wearing contact lenses depend not only upon the substance, but also on factors including the form of the substance, characteristics and duration of the exposure, the uses of other eye protection equipment, and the hygiene of the lenses. However, there may be individual substances whose irritating or corrosive properties are such that the wearing of contact lenses would be harmful to the eye. In those specific cases, contact lenses should not be worn. In any event, the usual eye protection equipment should be worn even when contact lenses are in place.

If material not on fire and not involved in fire: Keep material out of water sources and sewers. Build dikes to contain flow as necessary. Attempt to stop leak if without undue personnel hazard. /Polychlorinated biphenyls/

Personnel protection: Keep upwind. Avoid breathing vapors ... Do not handle broken packages unless wearing appropriate personal protective equipment. /Polychlorinated biphenyls/

/The worker in a confined space/ should wear appropriate protective equipment, and be connected by a lifeline harness to an outside worker. /Polychlorinated biphenyls/

For more Preventive Measures (Complete) data for Aroclor 1260 (17 total), please visit the HSDB record page.

3.0 [mg/m3]

330 [mg/m3]

2000 [mg/m3]

A mean Aroclor 1260 concentration of 0.944 ug/g (wet tissue) was found in the adipose tissue of 99 human corpses(1). Median levels of 0.35-1.6 mg/kg were found in the fat of human milk collected from 461 females from 6 nations between 1979-82(2). Mean Aroclor 1260 levels of 1814-2950 ng/g were detected in the adipose tissue of 175 samples collected in Kingston and Ottawa, Canada(3). EPA human monitoring program found PCB body pattern to be similar irrespective of source for non-occupationally exposed humans; PCB pattern resembled Aroclor 1260(4). The 2,3,4,5-PCBs are preferentially enriched in human milk with at least 2 rings substituted (>Cl4). Thus the PCB congeners from Aroclor 1016 would not be major contributors (only for Aroclor 1016, 1221)(4). Aroclor 1260 was also found in adult donors in Louisiana: 8 in 1980 had 0.59-2.33 ppm lipid; 10 in 1984 had 0.65-1.96 ppm lipid(4). PCB pattern in human milk produced on feeding contaminated milk (Aroclor 1260) is not the same as the original Aroclor. Enrichment occurred for: 2,2',3,4,4'5'-, 2,2',4,4',5,5'-hexa; 2,2',3,3',4,4',5'- and 2,2',3,4,4',5,5'-heptachlorobiphenyl(4).

Aroclor 1260 were found in the fat of human milk collected from 461 females from 6 nations between 1979-82 at median levels of 0.35-1.6 mg/kg(1).

The relationships among serum polychlorinated biphenyls (PCBs) concentration, serum lipids concentration, and adipose tissue PCBs concentration were studied in humans. Fasting blood samples were obtained from 173 capacitor workers with direct occupational exposure to Aroclor-1254, Aroclor-1242, and Aroclor-1260. Serum was analyzed for PCBs, albumin, triglycerides, and cholesterol. Serum PCBs ranged from 12 to 392 ppb for Aroclor-1242 and 4 to 129 ppb for Aroclor 1254 and 1260. Serum concentration of PCBs were significantly dependent on serum concentration of lipids, but not of albumin. The apparent contribution of cholesterol and its esters to PCB transport was nearly equal to their contribution to the total serum neutral lipids present.

There are no specific treatments for PCB poisoning, since it is not usually recognized until after substantial chronic exposure. Only preventing further exposure and treating the observed symptoms can be done. Acute inhalation can be treated by administering oxygen. (L4)

Acute parenteral administration of several commercial PCB mixtures (Aroclors 1242, 1248, 1254, and 1260) and a synthetic mixture of PCB congeners reflective of PCBs detected in human milk antagonized 2,3,7,8-TCDD /2,3,7,8-tetrachlorodibenzodioxin/-induced impairment of the immune response to SRBC /sheep red blood cells/ in mice at PCB:TCDD dose ratios > 1000:1 Aroclor 1232 had no effect on TCDD-induced immunotoxicity in these studies. Aroclor doses that antagonized the acute immunotoxicity of single doses of 0.0012 or 0.0036 mg/kg 2,3,7,8-TCDD ranged from about 1 to 50 mg/kg/day. Among seven individual PCB congeners examined for their ability to influence this immunotoxic action of single intraperitoneal doses of 0.0012 ug/kg 2,3,7,8-TCDD in mice (six hexachlorobiphenyls and one pentachlorobiphenyl with different chlorine substitution patterns), three were antagonistic (the 2,3,3',4,5,5'-, 2,3,3',4,5'- and 2,2',4,4',5,5'-congeners), and 4 showed no influence (the 2,3,3',4,4',5' -, 2,3',4,4',5',6-, 2,2',4,4',5,6'-, and 2,2',4,4',6,6'-congeners ). In these studies, doses of individual PCB congeners ranged from about 1 to 100 - 300 mg/kg. Oral co-exposure of pregnant mice to 244 mg/kg Aroclor 1254 and 0.020 mg/kg 2,3,7,8-TCDD, at an Aroclor:TCDD dose ratio of 12,200:1, completely antagonized TCDD-induced cleft palate formation in offspring. The complexity of interactions between PCBs and TCDD-induced developmental toxicity is illustrated by observations that, among one tetrachlorobiphenyl and two hexachlorobiphenyl congeners examined, one (the 2,3,3',4,4',5-congener) potentiated TCDD-induced cleft palate formation and the other two (the 2,2',4,4'- and 2,2',4,4',5,5'-congeners) antagonized TCDD's actions. Antagonism of TCDD-induced cleft palate formation in mouse offspring by 2,2',4,4'-tetraCB and 2,2',4,4',5,5'-hexaCB showed complex (i.e., inverted U-shape) relationships with dose. For example, no antagonistic effect (against a TCDD dose of 0.0015 ug/kg) was produced by 10-20 mg/kg doses of 2,2',4,4',5,5'-hexaCB, but antagonism increased with increasing 2,2',4,4',5,5'-hexaCB dose to a maximum (500 mg/kg), and then declined to no antagonism at 1,000 mg/kg 2,2',4,4',5,5'-hexaCB. 2,2',4,4',5,5'- HexaCB also antagonized TCDD-induced hydronephrosis in mouse offspring showing a similar inverted U-shape relationship with dose. In contrast, combined exposure of pregnant mice to 2,3,3',4,4',5-hexaCB and 2,3,4,7,8-pentachlorodibenzofuran appeared to additively produce hydronephrosis and cleft palate in the offspring. Several 13-week oral exposure studies have examined possible binary interactions between three PCB congeners (at several dietary concentrations delivering daily doses ranging from about 0.1 to 10 mg/kg/day) and 2,3,7,8-TCDD (at several dietary concentrations delivering daily doses ranging from about 0.00003 to 0.3 mg/kg/day) in influencing several end points in rats. The PCB:TCDD concentration ratios administered in these studies were selected to reflect relative concentrations in samples of human milk and fat. 2,2',4,4',5,5'-HexaCB and 2,3,7,8-TCDD showed joint additive action in decreasing thyroid hormone levels at 4 weeks, but synergistic action at 13 weeks, whereas 2,3,3',4,4',5-hexaCB and 3,3',4,4',5-pentaCB showed less-than-additive joint action with 2,3,7,8-TCDD in decreasing thyroid hormone levels. 2,2',4,4',5-Hexachlorobiphenyl did not influence TCDD-induced effects on body weight and thymus weight, and additively increased relative liver weight with TCDD, whereas 2,3,3',4,4',5-hexaCB and 3,3',4,4',5-pentaCB showed less-than-additive joint action with TCDD on these end points. 2,2',4,4',5,5'-hexaCB and 2,3,7,8-TCDD showed a distinct synergism in increasing hepatic porphyrin levels, but 2,3,3',4,4',5-hexaCB and 3,3',4,4',5-pentaCB showed no such synergism with 2,3,7,8-TCDD. All three of these congeners individually decreased hepatic levels of retinol and retinylpalmitate. In combination with TCDD, less-than-additive joint actions were noted, but TCDD doses used in these studies produced a near maximal response in decreasing retinoid levels

PCBs and methylmercury represent a combination of agents of public health concern that are potential neurotoxicants found in the complex mixture of biopersistent toxicants in contaminated fish from the U.S. Great Lakes and the Baltic Sea. Changes in neurological function or development from PCBs and methylmercury have been proposed to at least partly involve disruption of calcium homeostatic mechanisms in neural cells leading to changes in neurotransmitter release (e.g., dopamine) or cell damage. Exposure of rat striatal tissue for 4 hours with methylmercury alone at concentrations ranging from 1 to 40 uM or a 1:1 mixture of Aroclors 1254 and 1260 at concentrations ranging from 10 to 200 ppm resulted in a significant, dose-dependent depletion of tissue dopamine levels. /It has been/ noted that these concentrations were, in general, higher than those measured in samples of Great Lakes fish (0.84-1.9 ppm PCBs and 0.34 ppm mercury). Combined in vitro exposure of rat striatal tissue to methylmercury and this 1:1 mixture of Aroclors 1254 and 1260 (10-200 ppm) synergistically depleted tissue levels of dopamine. For example, combined exposure to 4 uM methylmercury and 200 ppm PCBs, or 10 uM methylmercury and 20, 40, 100, or 200 ppm PCBs, showed a significant statistical interaction (in an analysis of variance) indicative of synergistic effects on depleting tissue dopamine levels.

Simultaneous exposure of rats to Aroclor 1254 or 1260 and chemicals of environmental concern such as the pesticides mirex, photomirex, and/or kepone in the diet resulted in increased severity of the liver lesions attributed to exposure to chlorinated biphenyls alone. Induction of hepatic AHH activity by Aroclor 1254 in the diet of lactating rats was increased in an additive manner by simultaneous dietary exposure to polybrominated biphenyls such as Firemaster BP-6.

Pretreatment of male rats with Aroclor 1254 at a dose of 25 mg/kg i.p. for 6 days resulted in potentiation of the hepatotoxicity of inhaled carbon tetrachloride (CCl4) as evidenced by a decrease in liver glucose-6-phosphatase and elevations of serum glutamic oxalacetic transaminase (SGOT), serum glutamic pyruvic transaminase (SGPT), isocitrate dehydrogenase, and sorbitol dehydrogenase. Aroclor 1254 alone did not demonstrate hepatotoxicity. Aroclor 1254 administration resulted in large increases in cytochrome c reductase, cytochrome P-450 (448) AND P-Nitroanisole demethylation. Subsequent exposure to CCl4 vapor resulted in over 70% decreases in the latter two parameters. The potentiation was dose-dependent with a dose of 5 mg/kg or higher being effective. Aroclor 1260 administration gave results similar to those of Aroclor 1254, but Aroclor 1221 enhanced CCl4 toxicity to a lesser extent.

The aim of this study was to determine the effects of subchronic exposure to complex mixtures of polyhalogenated aromatic hydrocarbons (PHAHs) on the thyroid hormone and retinoid status in female Sprague-Dawley rats and to investigate the predictability of these effects by the toxic equivalency factor (TEF) concept. In the first experiment, the focus was on a complex dioxin-like PHAH mixture, which covered > 90% of the total toxic equivalents (TEQ) present in Baltic herring. In the second experiment, the contribution of non-dioxin-like polychlorinated biphenyls (PCBs) was investigated by testing the commercial PCB mixture Aroclor 1260, its 0-1 ortho and 2-4 ortho fractions and the reconstituted 0-4 ortho Fraction. Hepatic retinoid levels were severely decreased ( approximately 70%) after treatment with the dioxin-like PHAH mixture, similar to the effect of a TEQ equivalent dose of 1 ug 2,3,7,8-TCDD/kg bw/week. However, the TEF concept failed to predict the effect on plasma retinol; a decrease (21%) was observed after treatment with the PHAH mixture, whereas an increase (21%) was found after treatment with TCDD. A more severe decrease of total thyroid hormone in plasma was observed after exposure to the PHAH mixture compared to treatment with TCDD ( approximately 60% vs. 38%). The discrepancy found between the predicted and observed effects for plasma retinol and thyroid hormone is possibly due to an additional effect of hydroxylated PCBs, formed from metabolizable PCBs present in the PHAH mixture. Aroclor 1260 and its fractions did not significantly alter the retinoid and thyroid hormone status at the dose levels tested ...

The most common health effects of PCBs are skin conditions such as chloracne and rashes. Chronic PCB exposure has also been shown to cause liver, stomach and kidney, damage, jaundice, edema, anemia, changes in the immune system, behavioral alterations, and impaired reproduction. (L4)

LD50 Colinus virginianus (Northern bobwhite) oral 747 mg/kg for 5 days on treated diet plus 3 days untreated

LD50 Anas platyrhynchos (mallard) oral 1,975 mg/kg for 5 days on treated diet plus 3 days untreated

LD50 Anas platyrhynchos (mallard) oral >2 mg/kg

LD50 Phasianus colchicus (ring-necked pheasant) oral 1,260 mg/kg for 5 days on treated diet plus 3 days untreated

For more Ecotoxicity Values (Complete) data for Aroclor 1260 (59 total), please visit the HSDB record page.

TERRESTRIAL FATE: PCBs, such as Aroclor 1260, are mixtures of different congeners of chlorobiphenyl and the relative importance of the environmental fate mechanisms generally depends on the degree of chlorination(1). The approximate distribution of chlorinated biphenyls in Aroclor 1260 is: <0.3% tri-, <0.3% tetra-, 9.2% penta-, 46.9% hexa-, 36.9% hepta-, 6.3% octa-, and 0.7% nonachlorobiphenyl(2). Based on a classification scheme(3), log Koc values of 4.8 to 6.8(4), indicate that Aroclor 1260 is expected to be immobile in soil(SRC). Volatilization of Aroclor 1260 from moist soil surfaces is expected to be an important fate process(SRC) given a Henry's Law constant of 3.36X10-4 atm-cu m/mole(5). However, adsorption to soil is expected to attenuate volatilization(SRC). Aroclor 1260 is not expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 4.05X10-5 mm Hg(6). Screening tests indicate that Aroclor 1260 is resistant to aerobic biodegradation in soils(7). However, anaerobic conditions will support limited biodegradation of Aroclor 1260. Reductive dechlorination of Aroclor 1260 was investigated in anaerobic slurries of estuarine sediments from Baltimore Harbor, Baltimore MD(8). The sediment slurries were amended with 800 ppm Aroclor 1260 with and without the addition of 350 uM 2,3,4,5-tetrachlorobiphenyl (2,3,4,5-CB) or 2,3,5,6-tetrachlorbiphenyl (2,3,5,6-CB) and incubated at 30 °C under methanogenic conditions(8). After 6 months, extensive meta dechlorination and moderate ortho dechlorination of Aroclor 1260 occurred in all incubated cultures except for sterilized controls(8). Overall, total chlorines per biphenyl decreased by up to 34%(8).

AQUATIC FATE: Based on a classification scheme(1), log Koc values of 4.8 to 6.8(2), indicate that Aroclor 1260 is expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is expected(3) based upon a Henry's Law constant of 3.36X10-4 atm-cu m/mole(4). Using this Henry's Law constant and an estimation method(3), volatilization half-lives for a model river and model lake are 11 hours and 9.4 days, respectively(SRC). However, volatilization from water surfaces is expected to be attenuated by adsorption to suspended solids and sediment in the water column. The estimated volatilization half-life from a model pond is 37 months to 198 years if adsorption is considered(5). According to a classification scheme(6), log BCFs 5.28 and 5.57 in fathead minnow(7) and in mullet(8), suggest the potential for bioconcentration in aquatic organisms is very high(SRC). PCB's, including Aroclor 1260 are chemically very inert and are stable to conditions of hydrolysis and oxidation(9). The higher chlorinated congeners in Aroclor 1260 are susceptible to reductive dechlorination by anaerobic microorganisms found in aquatic sediments(10). Reductive dechlorination of Aroclor 1260 was investigated in anaerobic slurries of estuarine sediments from Baltimore Harbor, Baltimore MD(11). The sediment slurries were amended with 800 ppm Aroclor 1260 with and without the addition of 350 uM 2,3,4,5-tetrachlorobiphenyl (2,3,4,5-CB) or 2,3,5,6-tetrachlorbiphenyl (2,3,5,6-CB) and incubated at 30 °C under methanogenic conditions(11). After 6 months, extensive meta dechlorination and moderate ortho dechlorination of Aroclor 1260 occurred in all incubated cultures except for sterilized controls(11). Overall, total chlorines per biphenyl decreased by up to 34%(11).

Aroclor 1260 analyses of ready-to-eat foods collected in markets of 20 US cities as conducted by the US FDA as part of Total Diet Studies for adults found Aroclor 1260 in one of 360 foods composites (positive detection in meat-fish-poultry category) for fiscal year 1978(1).

ENVIRONMENTAL: Aroclor 1260 were found in the fat of human milk collected from 461 females from 6 nations between 1979-82 at median levels of 0.35-1.6 mg/kg(1). Human breast milk samples from 31 Egyptian women collected in May 1987 were analyzed for a number of different chlorinated contaminants(2). Aroclor 1254 and Aroclor 1260 were not detected (detection limit = 0.001 ppm) in any of the samples analyzed during this experiment(2).

The mechanism of action varies with the specific PCB. Dioxin-like PCBs bind to the aryl hydrocarbon receptor, which disrupts cell function by altering the transcription of genes, mainly be inducing the expression of hepatic Phase I and Phase II enzymes, especially of the cytochrome P450 family. Most of the toxic effects of PCBs are believed to be results of Ah receptor binding. Other PBCs are believed to interfere with calcium channels and/or change brain dopamine levels. PCBs can also cause endocrine disurption by altering the production of thyroid hormones and binding to estrogen receptors, which can stimulate the growth of certain cancer cells and produce other estrogenic effects, such as reproductive dysfunction. They will bioaccumulate by binding to receptor proteins such as uteroglobin. (A3, A4, A30, A66)

/BIRDS and MAMMALS/ Splenic atrophy was observed in groups of cockerels fed diets containing 400 mg/kg Phenochlor DP6, Clophen A60, or Aroclor 1260 for 60 days.

/BIRDS and MAMMALS/ ... A significant stimulation of thyroid growth /was also found/ after feeding bobwhite quail a diet containing 5, 50, or 500 mg Aroclor 1260/kg for 4 months ... Ring doves /were raised/ on either a low iodine or normal diet. Insufficient iodine caused thyroid hyperplasia. This hyperplasia was reversed within 7 days by a single dose of 3,4,3',4'-tetrachlorobiphenyl at 60 mg/kg bw. The PCB treatment also caused a significant decrease in core body temperature and serum total thyroxine (T4) and triiodothyronine (T3). No effect, other than decreased serum T3 and T4, was caused by dosing doves with PCBs on a diet containing normal iodine levels.

/BIRDS and MAMMALS/ Captive breeding (n = 25 pairs) and nonbreeding (n = 25) American kestrels were exposed to a mixture of polychlorinated biphenyls (PCBs) (Aroclor 1248:1254:1260) through their diet of day-old cockerels. Kestrels ingested approximately 7 mg/kg body weight each day of PCBs, and this dosage resulted in environmentally relevant total PCB residues in eggs (geometric mean of 34.1 ug/g). An equal number of unexposed birds served as controls ... Exposure to PCBs altered the size of brood patches in American kestrels. PCB-exposed male and female nonbreeders had two of three brood patches that were larger than those of control nonbreeders. Breeding males exposed to PCBs had smaller patches than controls, whereas PCB-exposed female kestrels had one larger and one smaller patch than controls. Patch sizes were not related to total PCB residue levels in eggs of exposed birds. Brood patches were not related to various incubation behaviors or hatching success in either control or PCB-exposed kestrels.

/BIRDS and MAMMALS/ This study found abnormalities in multiple reproductive stages in captive American kestrels (Falco sparverius) when exposed to polychlorinated biphenyls (PCBs) through dietary (PCB-spiked (Aroclor 1248:1254:1260) food (5-7 ug/g body weight per day) for 100 days) and in ovo exposure ... Effects of maternal (only female exposed) and paternal (only male exposed) in ovo PCB exposure were investigated. Maternal F1 eggs contained predicted total PCB concentrations of 0.34 ug/g. Specific abnormalities occurred more frequently during dietary F0 exposure, particularly aggressive courtship interactions, clutch abandonment, occurrences of cracked eggs, and developmental effects. Multiple developmental effects were more pronounced during than after dietary PCB exposure of adults, and although these effects were limited, nevertheless they occurred in the F1 maternal and F1 paternal pairs. However, the incidence of multiple deformities throughout the breeding season increased dramatically from 1998 (13%) to 1999 (56%) in F0 PCB-exposed pairs. Developmental abnormalities were unlikely to be attributed to the extrinsic factors of disease, genetics, or nutritional (vitamin D3) deficiencies, but rather to adverse changes in parental behavior and intrinsic factors involving altered genetic material and PCB exposure. Readily cleared PCB congeners may induce specific types of behavioral and developmental abnormalities, but persistent congeners and metabolites are likely producing (1) odd laying patterns, (2) odd laying patterns, (2) developmental effects including embryonic underdevelopment and edema, and (3) increased incidences of multiple deformities within a clutch.

Aroclor 1260 was detected in beet (Beta vulgaris) leaves at 52 ug/kg and roots at 35 ug/kg, in turnip (Brassica rapa) leaves at 27 and 52 ug/kg and roots at 20 and 204 ug/kg, and in bean (Phaseolus vulgaris) leaves at 107, stems at 36, pods at 98 and 0 ug/kg in seeds, all grown in soil amended with lake sediment contaminated with Aroclors 1248, 1254 and 1260(1). Aroclor 1260 was detected in 100% of Ceratophyllum demersum (Rigid hornwort), 66% of Lemna Spp (duck weed) and 66% of Potamogeton pectinatus (fennel pondweed) at 0.11-0.73, 0.06-0.22 and 0.36-0.61 ng/g wet weight in plants sampled 1997 to 1998 from the aquatic ecosystem of Lake Manzala, Egypt(2).

The isomer specific composition of 13 technical PCB formulations of different origin and of pine needles was analyzed using GC/MS and HRGC/HRMS. Nonachlorinated biphenyls were identified in 11 among 13 formulations analyzed, with the highest abundance found for highly chlorinated ones (Aroclors 1268 and 1260, Chlorofen, Sovol, Kanechlors 600 and 500, Delor 106, Clophen A60). Decachlorobiphenyl was identified only in Aroclor 1268, Clophen A60, Aroclor 1260 and Chlorofen, comprising, respectively, 8.9, 2.8, 1.3 and 0.82% of the total bulk of nona- and decaCBs detected. Nona- and decaCB were detected in pine needles in Poland with the highest concentrations found at the sites neighboring to a former production sites of the Polish PCB formulations, while in pine needles collected around the Tokyo Bay nona- and decacCB were detected only in four of 10 sites and the concentrations corresponded to those found at the rural areas of Poland.

Persons in charge of vessels or facilities are required to notify the National Response Center (NRC) immediately, when there is a release of this designated hazardous substance, in an amount equal to or greater than its reportable quantity of 1 lb or 0.454 kg. The toll free number of the NRC is (800) 424-8802. The rule for determining when notification is required is stated in 40 CFR 302.4 (section IV.D.3.b).

Formerly used in electrical transformers, hydraulic fluids, plasticizer in synthetic resins and dedusting agents. Although the production and sale was discontinued in late 1977, it is still present in many of the transformers and capacitors now in use.

As of Jan 1979, Aroclors /including Aroclor 1260/ are no longer used in the production of capacitors and transformers. Nevertheless, the life expectancy of transformers containing PCBs is > 30 yrs and the life expectancy of capacitors ranges from 10 to 20 yrs, depending on the electrical application ... In 1981, an estimated 131,200 transformers containing PCBs were in service in the US, representing approx 1% of all operational transformers.

Summary of former end uses for various Aroclors:

PCBs were used as coolants and lubricants in transformers, capacitors, and other electrical devices (such as fluorescent lights and refridgerators) produced before 1977. PCBs may contaminate the air and water near hazardous waste sites. In addition, PCBs bioaccumulate in the environment and may be found in fish, meat, and dairy products. (L4)

Polychlorinated naphthalenes have also been identified in small quantities in /Aroclor 1260/.

PCDF Impurities in ppm: Cl3, 0.01; Cl4, 0.2-0.8; Cl5, 0.26-0.9; Cl6, 0.3-0.5; Cl7, 1.3. Toxic PCDF levels: 2,3,7,8-TCDF, 0.013 ppm; 1,2,3,4,8-/1,2,3,7,8-PECDF, 0.048; 2,3,4,7,8-PECDF, 0.056; 2,3,4,7,9-/1,2,3,4,7,8-PECDF, 0.5; 1,2,3,6,7,8-HXCDF, 0.12; 1,2,3,7,8,9-HXCDF, 0.19; 2,3,4,6,7,8-HXCDF, 0.027.

Concns of chlorinated dibenzofurans in commercial Aroclor mixtures: tetrachloro, 0.1-0.8 ug/g; pentachloro-, 0.3-3.6 ug/g; hexachloro-, 0.3-1.9 ug/g

(1982) Not produced commercially in USA

/Production/ discontinued in October 1977

Not used commercially in USA

Domestic sales in millions of pounds of Monsanto's Aroclor 1260 in the United States from 1957 to 1970 are as follows: 7.6 (1957); 6.0 (1958); 6.6 (1959); 7.3 (1960); 6.5 (1961); 6.6 (1962); 7.6 (1963); 8.5 (1964); 5.8 (1965); 5.9 (1966); 6.4 (1967); 5.3 (1968); 4.4 (1969); and 4.9 (1970).

PCBs /were/ ... prepared industrially by the chlorination of biphenyl with anhydrous chlorine in the presence of a catalyst such as iron filings or ferric chloride. The products are complex mixtures of chlorobiphenyls, whose degree of chlorination depends principally on the time of contact (12-36 hr) of the biphenyl with anhydrous chlorine. The crude product is blown with air, and a small amount of lime is added to remove hydrogen chloride and ferric chloride. The resulting chlorinated mixtures are batch-distilled to remove color and traces of hydrogen chloride and ferric chloride. /Polychlorinated biphenyls/

The approximate distribution of chlorinated biphenyls in Aroclor 1260 is: <0.3% tri-, <0.3% tetra-, 9.2% penta-, 46.9% hexa-, 36.9% hepta-, 6.3% octa-, and 0.7% nonachlorobiphenyl.

Aroclor 1260 is a polychlorobiphenyl mixture containing 60% chlorine. It is composed of 12% penta-, 38% hexa-, 41% hepta-, 8% octa-, and 1% nona-chlorobiphenyls.

Congener composition: Cl4, 1%; Cl5, 12%; Cl6, 38%; Cl7, 41%; Cl8, 8%

Composition: pentachlorobiphenyls 12%; hexachlorobiphenyls 38%; heptachlorobiphenyls 41%; octachlorobiphenyls 8%; nonachlorobiphenyl 1%.

Total US sales in 1970 counted to 33.2 million kg and comprised ... 2.2 million kg Aroclor 1260 ...

Aroclor 1260 is the formulation used mostly in large capacitors and transformers. Federal Register, AUG 1979.

The Aroclors are characterized by four digit numbers. The first two digits indicate that the mixture contains biphenyls (12), triphenyls (54) or both (25, 44); the last two digits give the weight percent of chlorine in the mixture (e.g., Aroclor 1242 contains biphenyls with approximately 42% chlorine). /Polychlorinated biphenyls/

... The average molecule in Aroclor 1260 has 6 substituent chlorines, but varying proportions of species with greater and lesser halogen content are found in the mixture depending on the manufacturing process.

For more General Manufacturing Information (Complete) data for Aroclor 1260 (6 total), please visit the HSDB record page.