3.2 Terrestrial Organisms
A few studies have analysed pyrethroids in poultry eggs, which are not environmentally representative [49, 50]. Low levels of λ-cyhalothrin [51], tefluthrin,
cyfluthrin and cypermethrin [52] have been reported in eggs and carcasses of
wild grey partridges.
A more in-depth study assessed the presence of pyrethroids in 123 unhatched
eggs from 16 species of wild birds from Doñana (nature reserve in southwestern
Spain) and surrounding areas [53]. Pyrethroids were detected in 93% of the eggs.
The highest mean values of contamination belonged to samples of black-headed
gull (162 ng/g lw), gull-billed tern (61.5 ng/g lw) and black kite (48.5 ng/g lw). The
lowest means were found for purple heron (1.49 ng/g lw), glossy ibis (1.59 ng/g lw)
and black-winged kite (1.93 ng/g lw). The total range was between not detected
and 324 ng/g lw. The many factors for this variation could include the feeding
habits, as previously described for other lipophilic contaminants [54, 55], body
condition, age, habitat and migratory behaviour [56].
Although comparing these levels to the studies on poultry eggs could be
far-fetched, it is interesting to notice the difference in the pyrethroid profiles.
Only bifenthrin or cypermethrin were detected in the poultry eggs [49, 50] as a
result of a specific pesticide treatment. However, wild bird eggs should reflect
the variety of pyrethroids in the environment. The samples from Doñana showed
12 individual pyrethroids [53], eggs of wild grey partridges contained λ-cyhalothrin
[51], and the carcasses of the same species contained cyfluthrin, cypermethrin
and tefluthrin [52].
The eggs from Doñana were also tested for halogenated flame retardants
[54]. Flame retardants were found in 100% of the samples, similar to the 93% for
pyrethroids. Unlike POPs, pyrethroids have low environmental persistence
( 90 days) [2], but their massive use makes them constantly present. PBDE and
dechlorane concentrations were in the same range as pyrethroids.
Fenpropathrin, fluvalinate and resmethrin were not detected in the eggs from
Doñana [53]. Cypermethrin, λ-cyhalothrin and bifenthrin were found in over 75%
of the samples. Tetramethrin, permethrin, fenvalerate and cyfluthrin occurred in
about half of the samples. Deltamethrin and phenothrin were detected in about a
quarter of them.
The species were divided into four categories according to their diet: terrestrial,
feeding from terrestrial ecosystems; anthropogenic, including a proportion of food
from human sources; aquatic, feeding from aquatic ecosystems; and herbivorous,
feeding on plants and algae [53]. Eggs of species with anthropogenic feeding habits
were more contaminated, followed by eggs of birds of the aquatic feeding category.
This suggests that dietary intake might play an important role in the bioaccumulation
of pyrethroids. It is also consistent with the higher contamination in urban areas
and the aquatic ecosystems being easily contaminated via run-off.
Bioavailability and Bioaccumulation of Pyrethroid Insecticides in Wildlife and. . .
213
A few studies have analysed pyrethroids in poultry eggs, which are not environmentally representative [49, 50]. Low levels of λ-cyhalothrin [51], tefluthrin,
cyfluthrin and cypermethrin [52] have been reported in eggs and carcasses of
wild grey partridges.
A more in-depth study assessed the presence of pyrethroids in 123 unhatched
eggs from 16 species of wild birds from Doñana (nature reserve in southwestern
Spain) and surrounding areas [53]. Pyrethroids were detected in 93% of the eggs.
The highest mean values of contamination belonged to samples of black-headed
gull (162 ng/g lw), gull-billed tern (61.5 ng/g lw) and black kite (48.5 ng/g lw). The
lowest means were found for purple heron (1.49 ng/g lw), glossy ibis (1.59 ng/g lw)
and black-winged kite (1.93 ng/g lw). The total range was between not detected
and 324 ng/g lw. The many factors for this variation could include the feeding
habits, as previously described for other lipophilic contaminants [54, 55], body
condition, age, habitat and migratory behaviour [56].
Although comparing these levels to the studies on poultry eggs could be
far-fetched, it is interesting to notice the difference in the pyrethroid profiles.
Only bifenthrin or cypermethrin were detected in the poultry eggs [49, 50] as a
result of a specific pesticide treatment. However, wild bird eggs should reflect
the variety of pyrethroids in the environment. The samples from Doñana showed
12 individual pyrethroids [53], eggs of wild grey partridges contained λ-cyhalothrin
[51], and the carcasses of the same species contained cyfluthrin, cypermethrin
and tefluthrin [52].
The eggs from Doñana were also tested for halogenated flame retardants
[54]. Flame retardants were found in 100% of the samples, similar to the 93% for
pyrethroids. Unlike POPs, pyrethroids have low environmental persistence
( 90 days) [2], but their massive use makes them constantly present. PBDE and
dechlorane concentrations were in the same range as pyrethroids.
Fenpropathrin, fluvalinate and resmethrin were not detected in the eggs from
Doñana [53]. Cypermethrin, λ-cyhalothrin and bifenthrin were found in over 75%
of the samples. Tetramethrin, permethrin, fenvalerate and cyfluthrin occurred in
about half of the samples. Deltamethrin and phenothrin were detected in about a
quarter of them.
The species were divided into four categories according to their diet: terrestrial,
feeding from terrestrial ecosystems; anthropogenic, including a proportion of food
from human sources; aquatic, feeding from aquatic ecosystems; and herbivorous,
feeding on plants and algae [53]. Eggs of species with anthropogenic feeding habits
were more contaminated, followed by eggs of birds of the aquatic feeding category.
This suggests that dietary intake might play an important role in the bioaccumulation
of pyrethroids. It is also consistent with the higher contamination in urban areas
and the aquatic ecosystems being easily contaminated via run-off.
Bioavailability and Bioaccumulation of Pyrethroid Insecticides in Wildlife and. . .
213