Selenium Hexafluoride

Excerpt from ERG Guide 125 [Gases - Toxic and/or Corrosive]:

In case of fire in the surroundings, use appropriate extinguishing media. In case of fire: keep drums, etc., cool by spraying with water.

Fresh air, rest. Half-upright position. Artificial respiration may be needed. Refer for medical attention.

ON FROSTBITE: rinse with plenty of water, do NOT remove clothes. Rinse skin with plenty of water or shower. Refer for medical attention .

First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then refer for medical attention.

· CALL 911. Then call emergency response telephone number on shipping paper. If shipping paper not available or no answer, refer to appropriate telephone number listed on the inside back cover.

· Do not touch or walk through spilled material.

Excerpt from NIOSH Pocket Guide for Selenium hexafluoride:

General First Aid:

(General first aid procedures)

· Wear positive pressure self-contained breathing apparatus (SCBA).

Biological Exposure Indices (BEI) [ACGIH] - Fluorides in urine = 2 mg/L prior to shift or 3 mg/L at end of shift; (Repeated measurements recommended.)

1.0 [mg/m3], inhalable fraction, as F[German Research Foundation (DFG)]

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. Cool all affected containers with flooding quantities of water. Apply water from as far a distance as possible. Use foam, dry chemical, or carbon dioxide. Do not apply water to point of leak in tank car or container. If fire becomes uncontrollable or container is exposed to direct flame, consider evacuation of one-third (1/3) mile radius.

Personnel protection: Wear positive pressure self-contained breathing apparatus when fighting fires involving this material. ... Wear appropriate chemical protective clothing.

SRP: Wastewater from contaminant suppression, cleaning of protective clothing/equipment, or contaminated sites should be contained and evaluated for subject chemical or decomposition product concentrations. Concentrations shall be lower than applicable environmental discharge or disposal criteria. Alternatively, pretreatment and/or discharge to a permitted wastewater treatment facility is acceptable only after review by the governing authority and assurance that "pass through" violations will not occur. Due consideration shall be given to remediation worker exposure (inhalation, dermal and ingestion) as well as fate during treatment, transfer and disposal. If it is not practicable to manage the chemical in this fashion, it must be evaluated in accordance with EPA 40 CFR Part 261, specifically Subpart B, in order to determine the appropriate local, state and federal requirements for disposal.

If selenium hexafluoride is leaked, the following steps should be taken: 1. Ventilate area of leak. 2. Stop flow of gas. If source of leak is a cylinder and the leak cannot be stopped in place, remove the leaking cylinder to a safe place in the open air, and repair the leak or allow the cylinder to empty.

Death

respiratory system

Chronic oral exposure to high concentrations of selenium compounds can produce a disease called selenosis. The major signs of selenosis are hair loss, nail brittleness, and neurological abnormalities (such as numbness and other odd sensations in the extremities). Animal studies have shown that selenium may also affect sperm production and the female reproductive cycle. (L619)

The substance can be absorbed into the body by inhalation.

inhalation

Oral (L619) ; inhalation (L619) ; dermal (L619)

Selenium readily substitutes for sulfur in biomolecules and in many biochemical reactions, especially when the concentration of selenium is high and the concentration of sulfur is low. Inactivation of the sulfhydryl enzymes necessary for oxidative reactions in cellular respiration, through effects on mitochondrial and microsomal electron transport, might contribute to acute selenium toxicity. Selenomethionine (a common organic selenium compound) also appears to randomly substitute for methionine in protein synthesis. This substitution may affect the structure and functionability of the protein, for example, by altering disulfide bridges. Inorganic forms of selenium appear to react with tissue thiols by redox catalysis, resulting in formation of reactive oxygen species and causing damage by oxidative stress. (L619)

Cough. Sore throat. Headache. Nausea. Shortness of breath. Burning sensation.

Redness. Pain. ON CONTACT WITH LIQUID: FROSTBITE.

Redness. Pain. Blurred vision. Severe deep burns.

In Animals: pulmonary irritation, edema

Short-term oral exposure to high concentrations of selenium may cause nausea, vomiting, and diarrhea. Brief exposures to high levels of elemental selenium or selenium dioxide in air can result in respiratory tract irritation, bronchitis, difficulty breathing, and stomach pains. Longer-term exposure to either of these air-borne forms can cause respiratory irritation, bronchial spasms, and coughing. (L619)

The following medical procedures should be made available to each employee who is exposed to selenium hexafluoride at potentially hazardous levels: 1. Initial Medical Examination: a) A complete history and physical examination: The purpose is to detect ... existing conditions that might place the exposed employee at increased risk, and to establish a baseline for future health monitoring. Examination of the respiratory tract should be stressed. b) 14" x 17" chest roentgenogram: Selenium hexafluoride causes lung damage in animals. Surveillance of the lungs is indicated. c) FVC and FEV (1 sec): Selenium hexafluoride is a severe pulmonary irritant in animals. Persons with impaired pulmonary function may be at increased risk from exposure. Periodic surveillance is indicated. 2. Periodic Medical Examination: The aforementioned medical examinations should be repeated on an annual basis, except that an x-ray is necessary only when indicated by the results of pulmonary function testing, or when signs and symptoms of respiratory disease occur.

/SIGNS AND SYMPTOMS/ Repeated contact with low concentrations of selenium hexafluoride may cause dermatitis, systemic toxicity characteristic of chronic selenium exposure, or fluorosis, a degenerative bone condition. Chronic exposure maybe more serious for children because of their potential longer latency period.

/SIGNS AND SYMPTOMS/ Tissue damage may be permanent; damage to the eyes may cause blindness. Exposure to selenium hexafluoride may result in electrolyte imbalance. Selenium hexafluoride may trigger electrolyte imbalance similar to that elicited by hydrogen fluoride, since selenium hexafluoride readily decomposes to selenium and hydrogen fluoride upon contact with moisture.

/SIGNS AND SYMPTOMS/ Selenium hexafluoride gas can cause eye irritation and damage to the cornea, exposure to the liquified gas can cause severe damage or blindness. Damage to the eyes is progressive while any unneutralized fluoride ion remains.

/SIGNS AND SYMPTOMS/ Selenium hexafluoride is a skin irritant. Contact with the liquified gas may cause burns, severe injury or frostbite. Burns are progressive while any unneutralized fluoride ion remains.

For more Human Toxicity Excerpts (Complete) data for SELENIUM HEXAFLUORIDE (6 total), please visit the HSDB record page.

/LABORATORY ANIMALS: Acute Exposure/ Acute /inhalation/ studies on the toxicity of selenium hexafluoride (SeF6), were carried out on the rabbit, guinea-pig, rat, and mouse at 100, 50, 25, 10, 5, and 1 ppm for 4 hr. Exposures down to and including 10 ppm (Ct = 40 ppm/hr) were uniformly fatal. Exposure to 5 ppm (Ct = 20 ppm/hr) resulted in pulmonary edema from which the animals recovered, and 1 ppm did not induce any grossly observable effects. However, with repeated exposure for 1 hr daily at 5 ppm, for 5 days, there were definite signs of pulmonary injury.

/LABORATORY ANIMALS: Acute Exposure/ The acute toxicity of selenium hexfluoride /is/ ... about one-half that of ozone (Ct = 25 ppm-hr, represents an LC50 for small laboratory rodents).

Selenium hexafluoride can affect the body if it is inhaled or if it comes in contact with the eyes or skin.

Highly toxic by inhalation.

The following list includes some common operations in which exposure to selenium hexafluoride may occur: 1) Use as a gaseous electric insulator, 2) use during production of selenium hydroxide and hydrofluoric acid, selenium and nitrogen.

D010; A solid waste containing selenium (such as selenium hexafluoride) may become characterized as a hazardous waste when subjected to the Toxicity Characteristic Leaching Procedure listed in 40 CFR 261.24, and if so characterized, must be managed as a hazardous waste.

Listed as a hazardous air pollutant (HAP) generally known or suspected to cause serious health problems. The Clean Air Act, as amended in 1990, directs EPA to set standards requiring major sources to sharply reduce routine emissions of toxic pollutants. EPA is required to establish and phase in specific performance based standards for all air emission sources that emit one or more of the listed pollutants. Selenium hexafluoride is included on this list.

(AZ) ARIZONA 10 ug/L /Selenium/

(NY) NEW YORK 10 ug/L /Selenium/

Selenium hexafluoride

1.67

15

Weapons of Mass Effect chemical material that, if stolen or diverted, can be converted into weapons using simple chemistry, equipment, or techniques.

(AZ) ARIZONA 45 ug/L /Selenium/

(CT) CONNECTICUT 10 ug/L /Selenium/

(ME) MAINE 35 ug/L /Selenium/

(MN) MINNESOTA 30 ug/L /Selenium/