Antimony

Antimony is a chemical element with symbol Sb and atomic number 51. [fusion_builder_container hundred_percent=”yes” overflow=”visible”][fusion_builder_row][fusion_builder_column type=”1_1″ background_position=”left top” background_color=”” border_size=”” border_color=”” border_style=”solid” spacing=”yes” background_image=”” background_repeat=”no-repeat” padding=”” margin_top=”0px” margin_bottom=”0px” class=”” id=”” animation_type=”” animation_speed=”0.3″ animation_direction=”left” hide_on_mobile=”no” center_content=”no” min_height=”none”][1] It is semimetallic chemical element, which can exist in two forms: the metallic form is bright, silvery, hard and brittle; the non-metallic form is a grey powder. Antimony is a poor conductor of heat and electricity; it is stable in dry air and is not attacked by dilute acids or alkalis. Antimony and some of its alloys expand on cooling. [2]

Use [3]

Antimony is mixed into alloys and used in lead storage batteries, solder, sheet and pipe metal, motor bearings, castings, semiconductors, and pewter. Antimony oxide is added to textiles, plastics, rubber, adhesives, pigments and paper to prevent them from catching fire. It is also used in paints, ceramics, ammunition and fireworks, and as enamels for plastics, metal, and glass. Antimony compounds also find medical uses.

Sources of Emission & Routes of Exposure

Sources of Emission [3]

•    Industry sources: Antimony oxides can be released as a by-product of smelting lead and other metals (emissions to air, land or water), and coal-fired power plants (emissions to air and land).
•    Diffuse sources: Refuse incinerators, small industrial facilities involving lead casting etc, and burning of fossil fuels, e.g. for home heating (emissions to air and land).
•    Natural sources: Antimony ores occur naturally in the earth’s crust. Volcanoes can release antimony oxides into the environment. Antimony is a common component of coal and petroleum.
•    Transport sources: Emissions result from vehicle exhaust.
•    Consumer products: Products such as plastics, textiles, rubber, adhesives, pigments and paper. Antimony alloys are found in solder, sheet, pipe, bearing and type metals, and castings.

Routes of Exposure [4]

•    As antimony is found naturally in the environment, the general population is exposed to low levels of it every day, primarily in food, drinking water, and air.
•    It may be found in air near industries that process or release it, such as smelters, coal-fired plants, and refuse incinerators.
•    In polluted areas containing high levels of antimony, it may be found in the air, water, and soil.
•    Workers in industries that process it or use antimony ore may be exposed to higher levels.

Health Effects [5]

Acute Effects

•    The only effects reported from acute exposure to antimony by inhalation in humans are effects on the skin and eyes. Skin effects consist of a condition known as antimony spots, which is a rash consisting of pustules around sweat and sebaceous glands, while effects on the eye include ocular conjunctivitis.
•    Oral exposure to antimony in humans has resulted in gastrointestinal effects.
•    Animal studies have reported effects on the lungs, cardiovascular system, and liver from acute exposure to high levels of antimony by inhalation.
•    Antimony is considered to have high acute toxicity based on short-term oral tests in rats, mice, and guinea pigs.

Chronic Effects

•    The primary effects from chronic exposure to antimony in humans are respiratory effects that include antimony pneumoconiosis (inflammation of the lungs due to irritation caused by the inhalation of dust), alterations in pulmonary function, chronic bronchitis, chronic emphysema, inactive tuberculosis, pleural adhesions, and irritation.
•    Other effects noted in humans chronically exposed to antimony by inhalation are cardiovascular effects (increased blood pressure, altered EKG readings and heart muscle damage) and gastrointestinal disorders.
•    Animal studies have reported effects on the respiratory and cardiovascular systems and kidney from chronic inhalation exposure. Oral animal studies have reported effects on the blood, liver, central nervous system (CNS), and gastrointestinal effects.
•    A National Toxicology Program (NTP) 14-day drinking water study of potassium antimony tartrate reported an increase in relative liver and kidney weights in the high dose group (females only).
•    A 13-week intraperitoneal injection study, also by the NTP, reported inflammation and/or fibrosis of the liver in mice dosed with potassium antimony tartrate.
•    EPA has not established a Reference Concentration (RfC) for antimony. However, EPA has established an RfC of 0.0002 milligrams per cubic metre (mg/m3) for antimony trioxide based on respiratory effects in rats.
•    The Reference Dose (RfD) for antimony is 0.0004 milligrams per kilogram body weight per day (mg/kg/d) based on longevity, blood glucose, and cholesterol in rats.

Reproductive/Developmental Effects

•    An increased incidence of spontaneous abortions, as compared with a control group, was reported in women working at an antimony plant.
•    Disturbances in the menstrual cycle were reported in women exposed to various antimony compounds in a metallurgical plant.  However, the study that reported these findings was unclear about concurrent exposure to other chemicals, nor did it provide the characteristics of the controls used.
•    Animal studies have reported a decrease in the number of offspring born to rats exposed to antimony prior to conception and throughout gestation.
•    Reproductive effects, including metaplasia in the uterus and disturbances in the ovum-maturing process, were reported in a rat study, following inhalation exposure.

Cancer Risk

•    In one human study, inhalation exposure to antimony did not affect the incidence of cancer in workers employed for 9 to 31 years.
•    Lung tumours have been observed in rats exposed to antimony trioxide by inhalation.
•    EPA has not classified antimony for carcinogenicity.

Safety [6]

First Aid Measures

•    Eye Contact: Check for and remove any contact lenses. In case of contact, immediately flush eyes with plenty of water for at least 15 minutes. Get medical attention.
•    Skin Contact: In case of contact, immediately flush skin with plenty of water. Cover the irritated skin with an emollient. Remove contaminated clothing and shoes. Wash clothing before reuse. Thoroughly clean shoes before reuse. Get medical attention.
•    Serious Skin Contact: Wash with a disinfectant soap and cover the contaminated skin with an anti-bacterial cream. Seek medical attention.
•    Inhalation: If inhaled, remove to fresh air. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. Get medical attention.
•    Serious Inhalation: Evacuate the victim to a safe area as soon as possible. Loosen tight clothing such as a collar, tie, belt or waistband. If breathing is difficult, administer oxygen. If the victim is not breathing, perform mouth-to-mouth resuscitation. Seek medical attention.
•    Ingestion: Do NOT induce vomiting unless directed to do so by medical personnel. Never give anything by mouth to an unconscious person. Loosen tight clothing such as a collar, tie, belt or waistband. Get medical attention if symptoms appear.

Expsoure Controls & Personal Protection

Engineering Controls

•    Use process enclosures, local exhaust ventilation, or other engineering controls to keep airborne levels below recommended exposure limits.
•    If user operations generate dust, fume or mist, use ventilation to keep exposure to airborne contaminants below the exposure limit.

Personal Protective equipment

The following personal protective equipment is recommended when handling antimony:
•    Splash goggles;
•    Lab coat;
•    Dust respirator (be sure to use an approved/certified respirator or equivalent);
•    Gloves.

Personal Protective Equipment in Case of a Large Spill:
•    Splash goggles;
•    Full suit;
•    Dust respirator;
•    Boots;
•    Gloves;
•    A self-contained breathing apparatus should be used to avoid inhalation of the product.
•    Suggested protective clothing might not be sufficient; consult a specialist BEFORE handling this product.

 

Regulation 

United States [7]

Exposure Limit Limit Values HE Codes Health Factors and Target Organs
OSHA Permissible Exposure Limit (PEL) – General Industry

See29 CFR 1910.1000 Table Z-1

0.5 mg/m3 TWA HE3 Chronic poisoning, functional disorders of the heart, degeneration of the heart muscle
OSHA PEL -Construction Industry

See29 CFR 1926.55 Appendix A

0.5 mg/m3 TWA HE3 Chronic poisoning, functional disorders of the heart, degeneration of the heart muscle
OSHA PEL – Shipyard Employment

See29 CFR 1915.1000 Table Z-Shipyards

0.5 mg/m3 TWA HE3 Chronic poisoning, functional disorders of the heart, degeneration of the heart muscle
National Institute for Occupational Safety and Health (NIOSH) Recommended Exposure Limit (REL) 0.5 mg/m3 TWA HE3 Heart muscle changes, heart disease
HE5 Spontaneous late abortion, premature birth, gynaecologic problems
HE10 Pneumoconiosis
American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Value (TLV) (2001) 0.5 mg/m3 TWA HE15 Skin and upper respiratory tract irritation
CAL/OSHA PEL 0.5 mg/m3 TWA HE15 Upper respiratory tract irritation

 

~h2Australia [3]

 

Safe Work Australia has set an eight-hour time weighted average (TWA) exposure limit for antimony of 0.5 mg/m3

 

Australian Drinking Water Guidelines (NHMRC and ARMCANZ, 1996):

Maximum of 0.003 mg/L (i.e. 0.000003 g/L)

 

~h1References 1.  https://en.wikipedia.org/wiki/Antimony2.  http://www.lenntech.com/periodic/elements/sb.htm 3.  http://www.npi.gov.au/resource/antimony-and-compounds4.  http://www.atsdr.cdc.gov/toxfaqs/tf.asp?id=331&tid=585.  http://www3.epa.gov/airtoxics/hlthef/antimony.html6.  http://www.sciencelab.com/msds.php?msdsId=99274387.  https://www.osha.gov/dts/chemicalsampling/data/CH_219100.html[/fusion_builder_column][/fusion_builder_row][/fusion_builder_container]