Insecticides human toxicity

Toxic to individual species or broadly hazardous Pesticides, fungicides, herbicides, insecticides, fumigants Toxic to humans Chronic or acute... 

Herbicides are designed to kill plants, not animals, and in general have lower mammalian toxicity than insecticides. Most herbicides interfere with plant hormones or enzymes that do not have any direct counterpart in animals. The most serious human health concerns have been related to contaminants of the primary chemical herbicide. There is an enormous amount of animal and some human toxicity data on 2,4-D and 2,4,5-T, but it now appears that much of this toxicity is caused by the contaminant TCDD. Military personnel exposed to Agent Orange, often contaminated with TCDD, reported birth defects, cancers, liver disease, and other illness. These concerns led to improvement in the manufacturing process to reduce TCDD contamination and ultimately to a reduction in use of 2,4-D herbicides. There is also concern that some herbicides may affect wildlife. For example, atrazine, a persistent herbicide, may adversely affect frogs. Persistence of herbicides may also... 

Malathion is an organophosphate cholinesterase inhibitor. Up to 8% of the topically applied dose may be absorbed. Malathion is used as a treatment for head lice, body lice and scabies. It effectively kills both the eggs and the adult lice. Malathion is an insecticide of relatively low human toxicity. However if malathion is used in an indoor environment, as it breaks down into malaoxon, it can be seriously and chronically poisonous. The safety of malathion in pregnancy and in lactating women and in children has not been established. 

The human toxicity of DDT has been a subject of intense study during the last 20-25 years. This led the World Health Organisation to prohibit the use of DDT as an insecticide. The long-term use of DDT resulted in the development of resistance to the insecticide in many pests (over 200 species). As a result, most developed countries initiated programmes for the gradual replacement of DDT. The manufacture of DDT, and consequently that of chloral, has been in gradual decline since 1963 [12, 13,17]. 

Pyrethrins and Pyrethroids Absorption Eluman toxicity Exposure symptoms Pesticide uses Exemplars Inhalation, ingestion Low human toxicities by themselves Irritating to mouth, nose, throat Insecticides and acaricides Pyrethrin, dimethrin, fenvalerate, permethrin, bifenthrin... 

Carbamates, first synthesized in the 1930s and commercialized in the 1960s, constitute the most recently developed class of anticholinesterase insecticides. Developed to replace the more dangerous CH and OP insecticides, their toxic principle derived from the effects on humans of the Calabar bean used in the West African trial by ordeal (Ecobichon 1997). Carbamates inhibit nervous tissue cholinesterases, but less irreversibly than OP insecticides, resulting in reduced toxicity (Ecobichon 1997). Common carbamate names include carbaryl, methomyl, and maneb. 

USE Insecticide acaricide. Human Toxicity A cholinesterase inhibitor. See Parathlon. 

One of the most toxic organophosphorus insecticides highly toxic by oral route effects are cumulative toxic symptoms are similar to those of other cholinesterase inhibitors and include nausea, vomiting, diarrhea, excessive salivation, blurred vision and pain in eye muscle, convulsion, coma, and respiratory failure probable lethal dose is estimated to be 5-10 g for adult humans. 

Low human toxicities by themselves Irritating to mouth, nose, throat Insecticides and acaricides... 

AMITON. During research on improved pesticides, scientists at the British firm Imperial Chemical Industries, Ltd. (ICI) discovered a class of organic compounds of phosphorus and sulfur having enhanced insecticidal properties. ICI gave the first of these compounds the trade name Amiton and shared news of its discovery with the scientific community in January 1955. Eventually, scientists recognized the exceptional human toxicity of Amiton, causing it to be withdrawn from many markets. 

The effects of pollution can be direct, such as toxic emissions providing a fatal dose of toxicant to fish, animal life, and even human beings. The effects also can be indirect. Toxic materials which are nonbiodegradable, such as waste from the manufacture of insecticides and pesticides, if released to the environment, are absorbed by bacteria and enter the food chain. These compounds can remain in the environment for long periods of time, slowly being concentrated at each stage in the food chain until ultimately they prove fatal, generally to predators at the top of the food chain such as fish or birds. 

Aldrin is insecticidally active as a contact and stomach poison against a wide range of soil pests. It is non-phytotoxic and does not cause taint. Aldrin is toxic to humans and animals and is now less used. 

W. J. Hayes, Jr., and E. R. Laws, Jr., eds.. Handbook of Pesticide Toxicology, Academic Press, Inc., San Diego, Calif., 1990. Three volume set provides detailed toxicological profiles of more than 250 insecticides, herbicides, and fungicides each compound described by identity, properties, and uses toxicity to humans, laboratory animals, domestic animals, and wildlife includes comprehensive coverage of diagnosis, treatment, prevention of injury, effects on domestic animals, wildlife, and humans - ISjOOO references. 

The two main federal agencies involved in the protection of human health and the environment are the Environmental Protection Agency (EPA) and the Occupational Safety and Health Administration (OSHA). EPA s principal concern is the protection of the environment, in most cases, the area outside of an industrial faciUty. There are 10 regional offices that carry out the regulatory functions of the agency (Table 1). Primary laws covered by EPA are the Clean Air Act Amendments (CAAA), the Clean Water Act (CWA), Resource Conservation and Recovery Act (RCRA), Comprehensive Environmental Response, Compensation, and LiabiUty Act (CERCLA), Toxic Substances Control Act (TSCA), and Eederal Insecticide, Eungicide, and Rodenticide Act (FIFRA). 

The edible parts of parsnips contain a chemical of insecticidal and strong synergistic nature. This chemical, present in a concentration of about 200 p.p.m., was isolated and identified as 5-allyl-l-methoxy -2, 3-methylene-dioxybenzene or myristicin. Its toxicity to various insects (fruit flies, etc.) was established and compared with pyrethrum and aldrin. A second chemical, identified as 2-phenylethyl isothiocyanate, was found in the edible parts of turnips and rutabaga, which also have been consumed for centuries by humans without obvious harm. 

Releases to air, land, and water occur primarily through its use as a restricted-use insecticide. The media of most importance for human exposure are contaminated air and soil. According to the Emergency Planning and Community Right-to-Know Act of 1986, 42 U.S.C. Section 11023, industries are required to submit chemical release and ofif-site transfer information to the EPA. The Toxic Release Inventory (TRI), which contains this information for 1987, became available in May of 1988. This database is updated yearly and provides a list of industrial production facilities and emissions. 

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