However, most studies on birds and their eggs have been conducted at exposures far higher than could be expected in the field. LD50 values from acute oral and from short-term dietary dosing indicate low toxicity of 2,4-D to birds.
Finlayson & Verrue (1985)conducted a chronic egg-to-fry test over 86 days using chinooksalmon in 2,4-D butoxyethanol ester solutions ranging up to118 µg/litre.
Volatility of 2,4-D derivatives
Widespread damage in vineyards and in other crops due to 2,4-D drift from sprayed wheat fields was reported by Robinson & Fox (1978) with two different damage patterns, one localized and the other widespread.
2.4-D levels in body tissues and fluids
Mutagenic effects Studies available at present are not adequate for the quantitive evaluation of the mutagenic effects of 2,4-D and its derivatives in short-term tests.
Rats 188.8.131.52 Effects on adult rats 184.108.40.206 Effects on offspring
The highly volatile ethyl, isopropyl, and butyl esters are beingreplaced by low-volatile esters or by amine salts to reduce crop damageresulting from 2,4-D vapour drift, and to decrease atmosphericpollution.
Cold-blooded animals 220.127.116.11 Amphibians 18.104.22.168 Fish
During recent years, the use of 2,4-D and 2,4,5-T in parks,forested recreation, and other areas frequently used by the public, hasbeen reduced in some countries because of increasing concern aboutpossible toxic effects, especially in relation to CDDs.
Epidemiological studies of the chronic effects of 2,4-D
Teratogenic and reproductive effects The no-observed-adverse-effect level for the teratogenic, embryotoxic, or fetotoxic effects of 2,4-D in mammals and birds appears to be about 10 mg/kg body weight per day.
Studies on mutagenic effects in workers exposed to 2,4-D
Disposal of Wastes Environmental pollution with 2,4-D may occur as a result of theproduction and disposal of 2,4-D, or of its by-products, and ofindustrial effluents.
Evidence on the carcinogenicity of 2,4-D
Acute toxic effects 2,4-D drug trials and studies on volunteers have shown that doses of between 5 and about 30 mg/kg body weight do not cause any acute toxic effects.