10 브롬화 비페닐

EYES: irrigate opened eyes for several minutes under running water. INGESTION: do not induce vomiting. Rinse mouth with water (never give anything by mouth to an unconscious person). Seek immediate medical advice. SKIN: should be treated immediately by rinsing the affected parts in cold running water for at least 15 minutes, followed by thorough washing with soap and water. If necessary, the person should shower and change contaminated clothing and shoes, and then must seek medical attention. INHALATION: supply fresh air. If required provide artificial respiration.

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 994,000(SRC), determined from a structure estimation method(2), indicates that decabromobiphenyl will be immobile in soil(SRC). Volatilization of decabromobiphenyl from moist soil surfaces is not expected to be an important fate process(SRC) given an estimated Henry's Law constant 4.2X10-8 atm-cu m/mole(SRC), using a fragment constant estimation method(3). Decabromobiphenyl is not expected to volatilize from dry soil surfaces(SRC) based on its vapor pressure of 3.98X10-10 mm Hg(4). A screening study using an activated sludge inoculum indicated that decabromobiphenyl is not biodegradable(5). Biodegradation data on polybrominated biphenyls such as decabromobiphenyl indicate these compounds are persistent in the environment, but may slowly be degraded under anaerobic conditions(6).

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 994,000(SRC), determined from a structure estimation method(2), indicates that decabromobiphenyl is expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is not expected(3) based upon an estimated Henry's Law constant of 4.2X10-8 atm-cu m/mole(SRC), using a fragment constant estimation method(4). According to a classification scheme(5), BCF values in the range of 0.6-5.4 measured in fish(6) suggests bioconcentration in aquatic organisms is low (SRC). Decabromobiphenyl is not expected to undergo hydrolysis in the environment due to the lack of hydrolyzable functional groups(7). Brominated biphenyls have been shown to undergo direct photolysis in solutions(7), suggesting that there is potential for direct photolysis in sunlit surface waters(SRC). A screening study using an activated sludge inoculum indicated that decabromobiphenyl is not biodegradable under aerobic conditions(6). Biodegradation data on polybrominated biphenyls such as decabromobiphenyl indicate these compounds are persistent in the environment, but may slowly be degraded under anaerobic conditions(7).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), decabromobiphenyl, which has a vapor pressure of 3.98X10-10 mm Hg at 25 °C(2), is expected to exist solely in the particulate phase in the ambient atmosphere. Particulate-phase decabromobiphenyl may be removed from the air by wet and dry deposition(SRC). Brominated biphenyls have been shown to undergo direct photolysis in solutions(3); however, it is unclear whether direct photolysis will occur for particulate phase decabromobiphenyl in the atmosphere.

The exact mechanism of toxicty of PBBs varies depending on the specific congener. The predominant interaction is believed to involve the aryl hydrocarbon receptor (AhR). PBBs bind to and activate the AhR, which in turn initiates the transcriptional upregulation of a number of genes, affecting biochemical and endocrine pathways, cell cycle regulation, morphogenesis, oxidative stress response, and various other processes. This results in the numerous toxic responses characteristic of PBBs. Some of the known induced genes include the cytochrome P-450-dependent monooxygenases CYP1A1 and CYP1A2. (L628)

/AQUATIC SPECIES/ In a short-term test (according to the ISO standard 6341) the immobilization of Daphnia magna (Crustacea) by technical decabromobiphenyl (Adine 0102) has been investigated. The following results were obtained after dissolution of the test material in DMSO because of its weak solubility in water. The maximum concentration resulting in 0% immobilization (24 hr): <2 mg/liter.

The concentration of decabromobiphenyl was <1 ug/kg wet weight from harbor seals collected from the North Sea(1). In whitebeaked dolphins from the North Sea, the concentration of decabromobiphenyl was <0.9 ug/kg wet weight(1). Decabromobiphenyl concentration was <0.5 ug/kg wet weight in sperm whales from the Atlantic Ocean(1).

Using a structure estimation method based on molecular connectivity indices(1), the Koc for decabromobiphenyl can be estimated to be 994,000(SRC). According to a classification scheme(2), this estimated Koc value suggests that decabromobiphenyl is expected to be immobile in soil(SRC).

/EPIDEMIOLOGY STUDIES/ ...Thyroid dysfunction in workers exposed for at least 240 hr to decabromobiphenyl and decabromobiphenyl oxide over a 4-year period. The average period of employment was 3.9 years, mean age, 34.7 years. Medical questionnaires, physical examinations, and laboratory tests were conducted. For exposure data see section 5.3. Thyroid nodules were seen in 3 out of 18 workers exposed for 3 years or longer. ...Reproductive effects /were also studied/ in the same PBB workers. A significant correlation was seen between length of employment and concentrations of follicle stimulating hormone (FSH). An abnormal FSH value was found in only one worker. A testicular cyst was found in one exposed worker, and epididymal nodules in two others. No testicular or epididymal nodules were seen among controls. No definite statement could be made concerning adverse effects on the prevalence of testicular and epididymal nodules, because of their prevalence in the general population. /Commercial mixture/

/EPIDEMIOLOGY STUDIES/ Thyroid function was investigated in a cohort of 35 male workers, selected from 86 identified workers exposed for at least 6 weeks, manufacturing decabromobiphenyl, decabromobiphenyl ether, and bromine. The study revealed four cases of primary hypothyroidism (11.4%), but none in 89 control subjects. The bromine compounds were the only common exposure. A significantly higher number of the exposed workers had detectable serum levels of DeBB (0.5-1340 ng/mL)... . /Commercial mixture/

/BIOMONITORING/ Effects in workers exposed to unspecified PBBs and/or decabromobiphenyl included increased serum thyrotropin, low or borderline low serum T4, and increased thyroid antimicrosomal antibody titers. A spectrum of thyroid effects has been observed in exposed rats, ranging from decreases in serum levels of serum T4 and T3 to histological and ultrastructural changes. Therefore, serum levels of T4 and/or other thyroid hormones are potential biomarkers of effects for PBBs. /Commercial mixture/