Pesticide Residues in Birds and Mammals - Pesticides: Evaluation of Environmental Pollution - page 427

Among raptors, because of their predatory lifestyle, often at the top of the food chain,
the situation of the Eurasian sparrowhawk in Spain (van Drooge et al. 2008); the Spanish
imperial eagle ( Aquila adalberti ) in Spain (Hernández et al. 2008); the northern aplomado
falcon ( Falco femoralis septentrionalis ) in Mexico (Mora et al. 2008); the European kestrel in
the Canary Islands, Spain (Mateo et al. 2000); the Eurasian hobby ( Falco subbuteo ) in Spain
(van Drooge et al. 2008); the white-backed vulture ( Gyps bengalensis ) in India (Muralidharan
et al. 2008); the white-tailed sea eagles ( Haliaeetus albicilla ) in Sweden (Helander et al. 2002)
and in the United Kingdom (Walker et al. 2010); the bald eagle in the United States (Buck et al.
2005; Cesh et al. 2008); the booted eagle ( Hieraaetus pennatus ) in Spain (Martínez-López et
al. 2007); the red kite ( Milvus milvus ) in Spain (Gómara et al. 2008); and the osprey in the
United States (Henny et al. 2003b) have also been considered to be of concern.
These are some of the wild bird species that were judged, at least, in “at risk” situation
for DDT residues, in scientific publications of the last 10 years. But the lack of data, results,
or conclusions for this period about other species, zones, regions, or countries should not
be, obviously, interpreted at any cost as free of problems derived from DDTs and/or other
recalcitrant POP insecticides and/or other pollutants in the environment.
Moreover, there are human health implications in some cases. In poultry ( Gallus gallus ),
the levels of OC pesticides were measured in home-produced eggs in Belgium, and it is
interesting to note that 17% of the egg samples had levels above the norm for ΣDDT, estab-
lished at 500 ng/g LW (Van Overmeire et al. 2009).
14.4.1.2 Mammals
Since the early works by Koeman and van Genderen (1966) or Holden and Marsden (1967),
among others, the OC pesticide levels in marine mammals have centered a lot of the atten-
tion of scientists (Aguilar et al. 2002; Rattner 2009). The literature on these compounds
in the blubber and other tissues of marine mammals across the world, especially from
the Arctic and more recently, the Antarctic regions, has been extensively and comprehen-
sively reviewed in the last 15 years (Norstrom and Muir 1994; Tanabe et al. 1994; Muir and
Norstrom 2000; Aguilar et al. 2002; Goerke et al. 2004; Riget et al. 2004, 2010; Braune et al.
2005; Fisk et al. 2005; Houde et al. 2005; Li and Macdonald 2005; Corsolini 2009; Sonne et al.
2009; Hoferkamp et al. 2010; Letcher et al. 2010; Sonne 2010).
Marine mammals are especially vulnerable to OC pesticides because these chemicals
accumulate efficiently in their thick blubber layers. They are long-lived animals, and ceta-
ceans and pinnipeds are thought to have a reduced capacity to metabolize DDTs and other
POPs when compared to terrestrial mammals, allowing a higher biomagnification through
the food web (Norstrom and Muir 1994; Tanabe et al. 1994; Houde et al. 2005). Polar bears
are an exception among marine mammals, as they have a superior OC biotransformation
capacity and have the highest levels of OC metabolites, although some of them have also
demonstrated ED activity (Braune et al. 2005; Letcher et al. 2009; Sonne 2010). Seals have
been considered particularly sensitive, since the natural stress in extreme cold environ-
ments is often more severe than in temperate regions, rendering this group of animals
more susceptible to the effects of anthropogenic pollutants (Schiavone et al. 2009).
In wild marine mammal populations, elevated POP levels have been associated with
pathological changes and abnormalities of various forms (skin lesions, skeletal deformities,
and liver and kidney damage), biochemical modifications (especially on hormonal and vita-
min A status), reproductive impairment (some of them related to ED activities), increased
tumor incidence and depression of the immune system, and, as a consequence of the lat-
ter, the occurrence of large die-offs among seal and cetacean species (Nyman et al. 2002;