Lindane (γ-Hexachlorocyclohexane)

2022-08-05

Lindane, also known as gamma-hexachlorocyclohexane, (γ-HCH), is an organochlorine chemical variant of hexachlorocyclohexane that has been used both as an agricultural insecticide and as a pharmaceutical treatment for lice and scabies.[1] It is a white solid that may evaporate into the air as a colourless vapour with a slightly musty odour. It is also available as a prescription (lotion, cream, or shampoo) to treat head and body lice, and scabies. Lindane has not been produced in the United States since 1976, but is imported for insecticide use. [2]


Uses [3]


Lindane is used as an insecticide on fruit and vegetable crops, for seed treatment, in forestry, and for livestock and pet treatment. Whilst it is no longer manufactured in the United States, it is still formulated there. Aerial application of the chemical is prohibited. Lindane is also used topically for the treatment of head and body lice and scabies; it is available in 1 percent preparations as a lotion, cream, or shampoo.


Sources and Routes of Exposure [2,3,4]


The most probable route of lindane exposure in humans is oral ingestion of food containing the insecticide. Lindane may also be inhaled, when released to the air during its formulation or use as an insecticide, from wind erosion of contaminated soil, or from release from hazardous waste sites. Lindane has been detected in groundwater and surface water samples collected near hazardous waste sites; however, the chemical has only very rarely been detected in drinking water supplies. Furthermore, lindane exposure can occur dermally, when applied as a lotion or shampoo to treat lice or scabies. Workers involved in the formulation or application of products containing γ-HCH may be exposed to higher concentrations. Once in the body, lindane is stored for a short time in body fat. It tends to leave the body very quickly through urine. Small amounts leave the body in faeces and when you exhale.


Health Effects [3]



Acute Effects


Acute inhalation exposure to lindane in humans has resulted in irritation of the nose and throat, effects on the blood (anaemia), and skin effects (elevated itchy patches of skin). The major effects noted from oral exposure to lindane in humans are effects on the nervous system, such as seizures and convulsions. Vomiting and nausea and effects on the cardiovascular and musculoskeletal systems have also been reported. Oral studies in animals have reported effects on the liver, kidney, immune, and nervous systems from acute lindane exposure.


Chronic Effects

Chronic exposure to lindane by inhalation in humans has been associated with effects on the liver, blood, and nervous, cardiovascular, and immune systems. Effects noted in animal studies from chronic oral exposure to lindane include effects on the blood (decrease in numbers of red and white blood cells), immune, and nervous systems, and the liver and kidney.


Reproductive/Developmental Effects


Limited information is available regarding the reproductive or developmental effects of lindane in humans. The one available study reported increased levels (not statistically significant) of follicle stimulating hormone and decreased levels of testosterone in men occupationally exposed to lindane. It is not known whether these hormonal changes could result in diminished reproductive capability. Animal studies have reported reproductive effects, such as decreased sperm count, increased testicular weight, and disruption of spermatogenesis from oral exposure to lindane. Disrupted ovarian cycling and reduced ovulation rate were reported in female animals exposed to lindane by gavage (experimentally placing the chemical in the stomach). Lindane has not been reported to cause developmental effects, such as birth defects, in animals via oral exposure.


Cancer Risk

No studies are available concerning carcinogenic effects in humans or animals following inhalation exposure to lindane. Lindane has been demonstrated to be a liver carcinogen in mice via oral exposure. EPA considers lindane to be a possible human carcinogen and has ranked it in EPA’s Group B2/C.


Safety [5]


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. WARM water MUST be used. Get medical attention immediately.
  • Skin Contact: In case of contact, immediately flush skin with plenty of water for at least 15 minutes while removing contaminated clothing and shoes. Cover the irritated skin with an emollient. Wash clothing before reuse. Thoroughly clean shoes before reuse. Get medical attention immediately.
  • Serious Skin Contact: Wash with a disinfectant soap and cover the contaminated skin with an anti-bacterial cream. Seek immediate medical attention.
  • Inhalation: If inhaled, remove to fresh air. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. Get medical attention immediately.
  • 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: If swallowed, 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 immediately.


Exposure Controls and 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 Protection

The following personal protective equipment should be used when handling lindane:

  • Splash goggles
  • Lab coat
  • Dust respirator (be sure to use an approved/certified respirator or equivalent)
  • Gloves

For large spills, the following should be used:

  • Splash goggles
  • Full suit
  • Dust respirator
  • Boots
  • Gloves.
  • A self-contained breathing apparatus should be used to avoid inhalation of the product.

Note: Suggested protective clothing might not be sufficient; consult a specialist BEFORE handling this product.


Regulation [5,6,7]



Exposure Limits

United States

American Conference of Governmental Industrial Hygienists (ACGIH) Threshold limit value – time-weighted average (TLV-TWA) = 0.5 mg/m3 for lindane.

National Institute for Occupational Safety and Health (NIOSH) Recommended exposure limit (REL) = 0.5 mg/m3 for lindane. Immediately dangerous to life and health (IDLH) limit = 50 mg/m3 for lindane.

Occupational Safety and Health Administration (OSHA) Permissible exposure limit (PEL) = 0.5 mg/m3 for lindane.

Environmental Protection Agency (EPA) Safe Drinking Water Act Maximum contaminant level (MCL) = 0.0002 mg/L for lindane.

Food and Drug Administration (FDA) Maximum permissible level in bottled water = 0.0002 mg/L for lindane. Action levels for lindane in food and in animal feed range from 0.1 to 0.5 ppm. Lindane is a prescription drug subject to labelling and other requirements.

Australia

Safe Work Australia TWA: 0.008 ppm and 0.1mg/m3

United Kingdom

NIOSH SKIN TWA: 0.5 (mg/m3)

Inhalation TWA: 0.1 (mg/m3)


References


http://en.wikipedia.org/wiki/Lindane

http://www.atsdr.cdc.gov/substances/toxsubstance.asp?toxid=138

http://www.epa.gov/ttn/atw/hlthef/lindane.html

http://www.epa.gov/osw/hazard/wastemin/minimize/factshts/hexagama.pdf

http://www.sciencelab.com/msds.php?msdsId=9924243

http://ntp.niehs.nih.gov/ntp/roc/twelfth/profiles/Lindane.pdf

http://www.safeworkaustralia.gov.au/sites/SWA/AboutSafeWorkAustralia/WhatWeDo/Publications/Documents/639/Workplace_Exposure_Standards_for_Airborne_Contaminants.pdf