Birds eggshell thinning

Although eggshell thinning attributable to DDE exposure has occurred in birds in the UK, the lethal and siiblethal effects of the cyclodiene pesticides aldrin, dieldrin and heptachlor are also believed to have contributed to the population effects, particularly in the case of the sparrowhawk and peregrine falcon. Following the withdrawal of DDT and the cyclodienes from use in the UK, Europe and North America, bird of prey populations that were severely affected have shown partial or complete recovery. ... 

The two examples just given are of localized effects associated with the acute toxicity of DDT and DDD to organisms in higher trophic levels. A more wide-ranging toxic effect associated with population decline was eggshell thinning caused by the relatively high levels of p,p -DDE in some predatory birds (see Table 5.7). 

Lundholm, E. (1997). DDE induced eggshell thinning in birds effects of p,p -iyDE on the calcium and prostaglandin metabolism of the eggshell gland. Comparative Biochemistry and Physiology 118C, 113-128. 

Eggshell thinning and deformities in certain species of fisheating birds... 

DDT is not highly toxic to birds when compared with fish. It is best known for the adverse effects on reproduction that is associated with the effects on eggshell thinning, especially DDE. Ratcliffe established the relationship between eggshell thickness and the widespread use of toxic... 

Organochlorine pesticides, PCBs and PCDDs/PCDFs caused the decline of several avian populations in the late 1960s, such as sparrow hawks and kestrels in Europe and North America (Newton, 1992). The effects of these compounds on birds were linked with direct mortality due to pollutants and reproductive performance, such as eggshell thinning and... 

The toxicity of lindane to bird species is very low to practically nontoxic. Eggshell thinning and reduced egg production has occurred in birds exposed to lindane. 

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