Pesticide groupings :: terrestrial ecosystems

Key Concerns:

There is a paucity of data on the effects of DDT on plant species which are indicative of an arable ecosystem. However the effects of DDT on wildlife, especially birds are well known. DDT causes lethality in birds, and one of its metabolites, DDE causes reproductive effects on birds by causing eggshell thinning (WHO 1989; ATSDR 2000). The extent of eggshell thinning varies between species, birds of prey are particularly susceptible (Wiemeyer and Porter 1970; Peakall et al. 1973; Lincer 1975) whereas gallinaceous birds are more resistant (Davison et al. 1976). As a consequence of these effects occurring in the field following recommended applications, DDT has since been banned in the UK. DDT is not acutely toxic to non-target invertebrates such as earthworms and honeybees. However the uptake of DDT by earthworms etc may pose an environmental hazard to predators (WHO 1989).

Additional Comments:

The use of DDT in the UK has been prohibited since 1986 as a result of the EU Council Directive 79/117/EEC (dated 21st December 1978) (HSE 2001). DDT compou nds are highly resistant to degradation or metabolism, they are readily bioaccumulated, and they continue to persist in the environment, several decades after their use being prohibited. Although levels are lower compared to the 1960s, DDT is still released to the atmosphere, either from its use in other countries or from the volatilisation of residues resulting from its previous use. DDT has recently been identified in air sampled from hazardous waste sites (ATSDR 2000).