RESUMO
Intensive land development as a result of the rapidly growing tourism industry in the "Riviera Maya" region of the Yucatan Peninsula, Mexico may result in contamination of groundwater resources that eventually discharge into Caribbean coastal ecosystems. We deployed two types of passive sampling devices into groundwater flowing through cave systems below two communities to evaluate concentrations of contaminants and to indicate the possible sources. Pharmaceuticals and personal care products accumulated in the samplers could only have originated from domestic sewage. PAHs indicated contamination by runoff from highways and other impermeable surfaces and chlorophenoxy herbicides accumulated in samplers deployed near a golf course indicated that pesticide applications to turf are a source of contamination. Prevention and mitigation measures are needed to ensure that expanding development does not impact the marine environment and human health, thus damaging the tourism-based economy of the region.
Assuntos
Monitoramento Ambiental/instrumentação , Água Doce/análise , Poluição Química da Água/análise , México , Praguicidas/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Esgotos/análise , Poluição Química da Água/prevenção & controleRESUMO
Seven pairs of southern elephant seals (Mirounga leonina) pups and their dams were sampled during the late weaning season among a breeding population of seals on Elephant Island in Antarctica. The blubber of the pups and the milk and blubber of their dams were analyzed for lipid-normalized concentrations of PCBs and organochlorines compounds in order to evaluate the lactational transfer of these contaminants. The lipid-normalized concentrations in these tissues were in the ppb range (i.e., ngg(-1) lipid). The levels of contaminants in southern elephant seals were low in comparison with residues that have been reported in pinnipeds from the northern hemisphere. The relative tissue concentrations of the analytes measured followed the pattern: SigmaDDT>mirex>SigmaPCB>Sigmachlordane>HCB>heptachlor epoxide>dieldrin>methoxychlor>SigmaHCH>other organochlorines. The very high DDE/SigmaDDT ratio (0.91) in the blubber of dams and pups was an indicative of long-term, extremely distant pollution. On the other hand, the relatively high levels of some other organochlorine pesticides (e.g. mirex, heptachlor epoxide, dieldrin, methoxychor) may reflect the continued use of these insecticides in developing countries located in the southern hemisphere. For most of the analytes measured, the lipid-normalized concentrations were lower in pup blubber and in the milk than in the maternal blubber. Lactational transfer rates were dependent on the logK(ow) (octanol/water partition coefficient) values of the analytes measured, less lipophilic compounds being more readily transferred to the pups by the lactational route.
Assuntos
Exposição Ambiental/análise , Hidrocarbonetos Clorados/análise , Resíduos de Praguicidas/análise , Bifenilos Policlorados/análise , Focas Verdadeiras/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Animais Recém-Nascidos , Regiões Antárticas , Feminino , Cadeia Alimentar , Hidrocarbonetos Clorados/metabolismo , Lactação , Resíduos de Praguicidas/metabolismo , Bifenilos Policlorados/metabolismo , Poluentes Químicos da Água/análiseRESUMO
Contamination of blubber tissues by organochlorine pesticides (OC) and PCBs was assessed in female and male pups and juveniles, as well as in adult females and subdominant adult males of the Southern elephant seal, Mirounga leonina, from Elephant Island in the Antarctic Peninsula. All residues of persistent organochlorine contaminants analyzed were found in blubber samples, except for beta-HCH, endosulfan II, endrin, heptachlor, and aldrin. The relative concentrations of the analytes detected were sigmaDDT > sigmaPCB > sigmachlordane > mirex > dieldrin > HCB> sigmaendosulfan > methoxychlor > sigmaHCHs > other OC pesticides. OC and PCBs concentrations were 1 or 2 orders of magnitude lower than those found in pinnipeds from northern hemisphere. The ratio sigmaDDT/sigmaPCB was higher in southern elephant seals. The relative importance of some OC residues indicates that pesticides used either currently or in the recent past in countries in the southern hemisphere are the sources of contamination in the Antarctic region. Data showed that concentrations of contaminants generally increased from pups < juveniles < adults and suggested that pups accumulated contaminants through transfer from the mother seals via transplacental and lactational routes.