Pesticide mammals

Diethyl 0-(3-methyl-5-pyrazolyl) phosphate (722) and 0,0-diethyl 0-(3-methyl-5-pyrazolyl) phosphorothioate (723) were prepared in 1956 by Geigy and they act, as do all organophosphates in both insects and mammals, by irreversible inhibition of acetylcholinesterase in the cholinergic synapses. Interaction of acetylcholine with the postsyn-aptic receptor is therefore greatly potentiated. 0-Ethyl-5-n-propyl-0-(l-substituted pyrazol-4-yl)(thiono)thiolphosphoric acid esters have been patented as pesticides (82USP4315008). 

Kerr SH, Brogdon JE. 1959. Relative toxicity to mammals of 40 pesticides. Agricultural Chemicals 14 44-45, 135. 

As explained in Section 5.2.3, p,p -DDE is much more persistent in food chains than either p,p -DDT or p,p -DDD, and dnring the 1960s when DDT was still extensively used, it was often the most abundant of the three compounds in birds and mammals found or sampled in the field. Since the widespread banning of DDT, very little of the pesticides has been released into the environment, and p,p -DDE is by far the most abnndant DDT residue found in biota. While discussing the ecological effects of DDT and related compounds, effects on population numbers will be considered before those on popnlation genetics (gene frequencies). 

Koeman, J.H. (Ed.) (1972). Side Effects of Persistent Pesticides and Other Chemicals on Birds and Mammals in the Netherlands. Report by the Working Group on Birds and Mammals of the Committee TNO for Research on Side Effects of Pesticides. TNO-Nieuws 27 527-632. 

Studies may be designed for estimating exposures to a wide array of wildlife, including birds, mammals and amphibians. Many regulatory requirements involve birds, and less emphasis is currently placed on other species. As regulatory requirements evolve, ecological risk assessments will be required for more species. This may require alternative approaches for food item analysis to allow estimates of pesticide ingestion. 

Pesticides, and especially OCPs (DDT and its metabolytes, HCH isomers, aldrine, dieldrin, heptachlor, etc.), are seen everywhere in mammals. Table 4.7 gives data on the death of higher vertebrates from causes linked to agricultural production in the USSR. About 40% of the accidental deaths of animals, and about 80% of birds, are due to pesticides. It is difficult to evaluate how many mammals in the environment die from pesticide contamination, since sick and weakened individuals fall prey to predators [6]. 

The negative role of pesticides in mammal life became clear several decades ago. OCP concentrations in the subcutaneous fat of seals (Pusa balded) from the Baltic Sea reached 300 mg/kg. Marine mammals living in the median latitudes of the northern hemisphere are more contaminated by DDT than animals of the southern hemisphere because of industrial development [6]. 

Mammals may die from pesticide poisoning not immediately, but many months later, when they more actively use their fat deposits, for example, when waking up after hibernating they are then poisoned by deposits of toxic substances in their fat [3,6]. 

Just like mammals, birds have a delayed reaction to lipotropHc pesticides such as OCPs and their metabolites. These toxic substances dissolve and accumulate in the fatty tissues of well-fed birds, and are comparably harmless in this form. However, once the bird starts using the stored fat (at the end of a long flight or when laying eggs), the substances are carried through the bloodstream to the brain, liver, or yolk of the egg, and poison all the systems [1]. In particular, well-fed raptors have lower DDE concentrations in their liver (0.5 mg/kg) than less well-fed (3.5 mg/kg) and emaciated birds (7.3 mg/kg) [6]. 

Several pesticides are embryotoxic, i.e., they pathologically affect the developing fetus. For example, it was established in long-term experiments on animals that polychlorpinen, phosalone and trichlorfon are embryotoxic to mammals, leading to stillbirths [A103]. 

Pesticides accumulate in fetal cells and reproductive organs in mammals, birds, and fish due to biochemical processes. This is noted especially often for OCPs, which were observed in large amounts (up to 6.8 mg/kg) in, for example, the sexual organs of hares, rabbits, pheasants, green-winged teals, and in white-eyed and red-headed ducks. They were found in animal embryos, as well as in black thrush eggs and in pheasant embryos and amniotic fluid (up to 73.0 mg/kg) [3]. 

Tables 14.6, 14.7, 14.8, 14.9 and 14.10 provide further insight into the comparative properties and toxicity of pesticides applied on organic and conventional farms to treat a given type of pest. Table 14.6 lists the primary pesticides approved for use on organic farms and their uses and target pests. Tables 14.7-14.10 again list the major organic pesticides, along with two or three conventional pesticide alternatives that are used by conventional farmers to manage the same pest problems. Tables 14.7 and 14.8 summarize the rates of application of these pesticides, while Tables 14.9 and 14.10 focus on relative measures of toxicity to mammals and other organisms.

So far, metabolic studies of about 30 synthetic pyrethroids, including their chiral and geometrical isomers, have been carried out in mammals [1], However, detailed metabolism data have not necessarily all been published in scientific journals. In some cases, the reports of joint World Health Organization-Food and Agricultural Organization (WHO/FAO) expert meetings on pesticide residues and the... 

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