Difference between revisions of "Dicofol"
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The main source of dicofol in the environment is its use as a pesticide used on a wide variety of fruits, vegetables, ornamentals and field crops. A total amount of over 2.700 tonnes of dicofol is used around the world each year, of which 290 tonnes is used in Western Europe. The only European countries which do allow its use are Belgium, Spain, Portugal and France. There are indications that through atmospheric transport the dicophol used in other continents might also affect the North Sea. | The main source of dicofol in the environment is its use as a pesticide used on a wide variety of fruits, vegetables, ornamentals and field crops. A total amount of over 2.700 tonnes of dicofol is used around the world each year, of which 290 tonnes is used in Western Europe. The only European countries which do allow its use are Belgium, Spain, Portugal and France. There are indications that through atmospheric transport the dicophol used in other continents might also affect the North Sea. | ||
| + | The degradation of dicofol in soil is moderately slow, it takes 30 to 60 days to half the concentration. In water systems and soils with a high organic matter content, halving its concentration may take up to 84 days. Like DDT, it also has a high affinity to lipids, which causes it to [[adsorption|adsob]] to organic particles rather than dissolve in water. It's also highly [[bioaccumulation|bioaccumulative]], and [[biomagnification|biomagnifying]], therefore it poses a greater threat to high trophic level species such as [[pollution and sea birds|birds]] and [[pollution and marine mammals|mammals]]. | ||
| + | Dicofol has been shown to be highly toxic for marine species. [[Pollution and pelagic fishes|Fish]] and show effects die by chronic exposure to concentrations above 0,0045 mg/l. Concentrations above 0,012 mg/l cause acute toxicity. | ||
| + | In birds dicofol can cause eggshell thinning at exposure 20 mg/kg food intake. It has also been shown to be a [[endocrine disrupting compounds|endocrine disrupting compound]] in birds. | ||
| − | + | ||
| − | + | Long-term effects include egg-shell | |
| + | thinning and effects on reproduction. In a study with a captive population of American krestels, birds | ||
| + | were dosed with 20 mg/kg of 99%-pure o,p'-dicofol. The eggs laid had significantly thinner shells than | ||
| + | those of the control birds. Feminisation of male embryos was confirmed by the presence of primordial germ cells in the male gonad. | ||
| + | two generation avian study (MacLellan et al., 1996) confirmed the results of | ||
| + | egg shell thinning by o,p’-dicofol and in addition revealed feminisation of male embryos already at a | ||
| + | level of 5 μg/g dicofol. Hatching success of the second generation females and males mating with | ||
| + | untreated birds showed adverse effects on reproduction success. MacLellan et al. (1997) found out that | ||
| + | dicofol exposure of parents had negative effects on the behaviour and mating success of the second | ||
| + | generation kestrels. | ||
Revision as of 11:02, 5 August 2009
Definition of =Dicofol:
Dicofol belongs to the group of organochlorine pesticides. It's produced from DDT; its chemical structure is therefore related to DDT and it has similar properties.[1]
This is the common definition for =Dicofol, other definitions can be discussed in the article
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Notes
The main source of dicofol in the environment is its use as a pesticide used on a wide variety of fruits, vegetables, ornamentals and field crops. A total amount of over 2.700 tonnes of dicofol is used around the world each year, of which 290 tonnes is used in Western Europe. The only European countries which do allow its use are Belgium, Spain, Portugal and France. There are indications that through atmospheric transport the dicophol used in other continents might also affect the North Sea.
The degradation of dicofol in soil is moderately slow, it takes 30 to 60 days to half the concentration. In water systems and soils with a high organic matter content, halving its concentration may take up to 84 days. Like DDT, it also has a high affinity to lipids, which causes it to adsob to organic particles rather than dissolve in water. It's also highly bioaccumulative, and biomagnifying, therefore it poses a greater threat to high trophic level species such as birds and mammals.
Dicofol has been shown to be highly toxic for marine species. Fish and show effects die by chronic exposure to concentrations above 0,0045 mg/l. Concentrations above 0,012 mg/l cause acute toxicity. In birds dicofol can cause eggshell thinning at exposure 20 mg/kg food intake. It has also been shown to be a endocrine disrupting compound in birds.
Long-term effects include egg-shell thinning and effects on reproduction. In a study with a captive population of American krestels, birds were dosed with 20 mg/kg of 99%-pure o,p'-dicofol. The eggs laid had significantly thinner shells than those of the control birds. Feminisation of male embryos was confirmed by the presence of primordial germ cells in the male gonad. two generation avian study (MacLellan et al., 1996) confirmed the results of egg shell thinning by o,p’-dicofol and in addition revealed feminisation of male embryos already at a level of 5 μg/g dicofol. Hatching success of the second generation females and males mating with untreated birds showed adverse effects on reproduction success. MacLellan et al. (1997) found out that dicofol exposure of parents had negative effects on the behaviour and mating success of the second
generation kestrels.
