RESUMO
Marine food webs are particularly vulnerable to oil spills if keystone species are impacted. To quantify lethal and sublethal toxicity in a key Holarctic forage fish, capelin embryos were exposed to Hibernia crude oil water accommodated fraction (WAF) produced at an oil-to-water ratio of 1:9 (v:v) and chemically-enhanced WAF (CEWAF) produced with the dispersant Corexit™ EC9500A at a dispersant-to-oil ratio of 1:10 (CEWAF H) or 1:50 (CEWAF L). Corexit alone yielded similar embryotoxicity to CEWAF. 10% CEWAF H, with total polycyclic aromatic hydrocarbons of 99.2⯵g/L, decreased embryo survival following 10â¯h of exposure, while continual exposed to 1% CEWAF L decreased hatching and heart rates. Concentrations down to 0.1% CEWAF L increased in a dose-dependent manner the transcript level of cytochrome P4501a1 (cyp1a1) in hatched larvae. These data indicate that embryo-larval survival of capelin is likely at risk if an oil spill coincides in space and time with spawning.
Assuntos
Mallotus (Planta) , Poluição por Petróleo , Petróleo , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Animais , Desenvolvimento Embrionário , Mallotus (Planta)/efeitos dos fármacos , Mallotus (Planta)/embriologia , Mallotus (Planta)/fisiologia , Petróleo/toxicidade , Poluentes Químicos da Água/toxicidadeRESUMO
The effects of petroleum aromatic hydrocarbons (PAHs) on the embryonic and larval life stages of teleosts have been extensively examined. However, very little work has been conducted on how spilled oil affects fish sperm and there is no related knowledge concerning oil dispersing agents. The objective of our study was to determine sperm performance of a teleost fish under direct exposure to different concentrations of WAF (water accommodated fraction) and CEWAF (chemically enhanced water accommodated fraction). Capelin sperm motility, swimming behaviour, and sperm fertilization ability were evaluated in a scenario of an oil spill untreated (WAF) and treated (CEWAF) with the dispersant Corexit® EC9500A. Sperm fertilizing ability was lower when exposed to CEWAF concentrations of 16.1â¯×â¯103⯵g/L total petroleum hydrocarbons and 47.9⯵g/L PAH, and when exposed to the dispersant alone. The mechanism responsible for this reduced fertilizing ability is not clear. However, it is not related to the percentage of motile sperm or sperm swimming behaviour, as these were unaffected. WAF did not alter sperm swimming characteristics nor the fertilizing ability. We suggest the dispersant rather than the dispersed oil is responsible for the decrease in the sperm fertilizing ability and hypothesize that the surfactants present in the dispersant affect sperm membrane functionality.
Assuntos
Peixes/fisiologia , Hidrocarbonetos/toxicidade , Lipídeos/toxicidade , Petróleo/toxicidade , Espermatozoides/efeitos dos fármacos , Tensoativos/toxicidade , Animais , Masculino , Poluentes Químicos da ÁguaRESUMO
BACKGROUND: This paper reports on an infection prevention and control surveillance survey of acute care facilities (ACFs) performed by the Provincial Infection Control Network of British Columbia. METHODS: A surveillance questionnaire was sent to all health care facilities that had access to an infection control professional. The questionnaire incorporated questions on organism-specific, disease-specific, and general surveillance activities. RESULTS: Questionnaires were returned from 47 of 51 (92%) of the ACFs surveyed. Participation in surveillance of methicillin-resistant Staphylococcus aureus-, vancomycin-resistant Enterococci-, and Clostridium difficile-associated disease ranged from 97% to 100%, but surveillance methodologies were inconsistent. Surgical-site infection surveillance did not correlate with the most commonly performed operations or with those procedures associated with higher morbidity and mortality from a postoperative infection. Considerable variation in data collection methods and case definitions was also identified. Surveillance for urinary tract infections, bloodstream infections, and ventilator-associated pneumonia was present in 28%, 51%, and 23% of responding ACFs, respectively. CONCLUSION: The current lack of a standardized surveillance system in British Columbia limits the ability of facilities to set appropriate benchmarks to assist in prioritizing and applying infection control interventions. The survey, however, has assisted in prioritizing implementation of surveillance activities and identifying the resources that would be required.