RESUMO
Produced water (PW) generated by oil companies is a highly impacting waste that contains chemicals such as metals and organic and inorganic compounds. Given its polluting potential, PW requires effective treatment before being discharged into the environment. Conventional treatments have limited efficiency in removing PW toxicity, so alternative approaches must be developed and standardized. In this context, treatment with adsorbent materials like magnetized vermiculite (VMT-mag) is highlighted. This work aimed to evaluate the efficiency of treatment with VMT-mag in reducing PW toxicity to aquatic biota. For this purpose, three aquatic species (the midge Chironomus riparius, the planarian Girardia tigrina, and the crustacean Daphnia magna) were exposed to untreated PW and to PW treated with VMT-mag at laboratory conditions. The assessed endpoints included mortality, growth, emergence, and developmental time of C. riparius; mortality, locomotion, feeding, and head regeneration of G. tigrina; and intrinsic population growth rate (r) and reproductive output of D. magna. The results showed that all the species exposed to raw PW were impaired: C. riparius had delayed development, G. tigrina had reduced locomotor activity and delayed head regeneration, and D. magna had reduced reproduction and delayed intrinsic population growth rate (r). Most of the analyzed parameters showed that treatment with VMT-mag diminished PW toxicity. Therefore, using VMT-mag to treat PW may be the key to reducing the PW effects on aquatic organisms.
Assuntos
Silicatos de Alumínio , Indústria de Petróleo e Gás , Eliminação de Resíduos Líquidos , Águas Residuárias , Poluentes Químicos da Água , Animais , Silicatos de Alumínio/química , Organismos Aquáticos , Daphnia , Água/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/toxicidade , Águas Residuárias/química , Eliminação de Resíduos Líquidos/métodos , Testes de ToxicidadeRESUMO
The water produced (PW) by the petroleum industry is a potential contaminant to aquatic biota, due to its complex mixture that may contain polycyclic aromatic hydrocarbons (PAHs), organic chemical compounds, including benzene, toluene, ethylbenzene and xylene (BTEX), metals and other components that are known to be toxic. The aim of this investigation was to examine the acute toxicity produced by a PW sample in aquatic organisms Vibrio fischeri and Daphnia similis prior to and after 4 treatments using advanced oxidative processes such as photocatalysis, photoelectrocatalysis, ozonation and photoelectrocatalytic ozonation. Data demonstrated that exposure to PW was toxic to both organisms, as evidenced by reduced luminescence in bacterium Vibrio fischeri and induced immobility in Daphnia similis. After treatment of PW with 4 different techniques, the PW remained toxic for both tested organisms. However, photoelectrocatalysis was more efficient in decreasing toxicity attributed to PW sample. Therefore, data demonstrate the importance of treating PW for later disposal in the environment in order to mitigate ecotoxicological impacts. Further photoelectrocatalysis appeared to be a promising tool for treating PW samples prior to disposal and exposure of aquatic ecosystems.
Assuntos
Organismos Aquáticos/efeitos dos fármacos , Indústria de Petróleo e Gás , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Poluentes Químicos da Água/toxicidade , Aliivibrio fischeri/efeitos dos fármacos , Animais , Daphnia/efeitos dos fármacos , Oxigênio/química , Petróleo/toxicidade , Testes de Toxicidade AgudaRESUMO
PURPOSE: Polycyclic aromatic hydrocarbons (PAHs) are contaminants with carcinogenic effects but little is known about their presence in environments surrounding oil drilling operations and spills or exposure levels in nearby communities. The objective of this study was to characterize PAH levels in people living near oil drilling operations in relation to fish consumption, occupation, source of water and other socio-demographic characteristics. METHODS: This pilot study examined PAH exposure by measuring 1-hydroxypyrene (1-OHP) in urine samples using high-performance liquid chromatography and fluorescence detection from 75 women and men in the Ecuadorian and Peruvian Amazon living near oil drilling operations and who answered a questionnaire collecting socio-demographic, occupational and dietary information. Data were analyzed using multiple linear regression models. RESULTS: The mean value of 1-OHP was 0.40 µmol/mol creatinine, 95% CI 0.32-0.46 µmol/mol creatinine. Women who used water from a surface source (for washing clothes or bathing) had almost twice the amount of 1-OHP in their urine (mean 1-OHP = 0.41 µmol/mol creatinine, 95% CI 0.28-0.54 µmol/mol creatinine, n = 23) as women who used water from either a well, a spring or rain (mean 1-OHP = 0.22 µmol/mol creatinine, 95% CI 0.11-0.34 µmol/mol creatinine, n = 6). Men who reported eating a bottom-dwelling species as their most commonly consumed fish (mean 1-OHP = 0.50 µmol/mol creatinine, 95% CI 0.36-0.64 µmol/mol creatinine, n = 31) had twice as much 1-OHP in their urine as men who reported a pelagic fish (mean 1-OHP = 0.25 µmol/mol creatinine, 95% CI 0.15-0.35 µmol/mol creatinine, n = 15), signaling either oral (fish consumption) or dermal (while standing in water fishing benthic species) exposure. CONCLUSIONS: More contact with surface water and benthic fish may result in higher levels of 1-OHP in human urine among the study population. Reducing the amount of oil and wastes entering the waterways in Andean Amazonia would be one way to reduce exposure.
Assuntos
Exposição Ambiental/análise , Peixes , Indústria de Petróleo e Gás , Pirenos/urina , Adolescente , Adulto , Animais , Dieta , Equador , Biomarcadores Ambientais , Monitoramento Ambiental/métodos , Poluição Ambiental/análise , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Peru , Projetos Piloto , RiosRESUMO
BACKGROUND: Mercury is a global contaminant with toxic, persistent effects on human health. Petroleum extraction is an important source of elemental mercury; little is known about human exposure levels near oil fields in the Amazon basin. OBJECTIVES: To characterize mercury levels in people living near oil production sites in the Peruvian and Ecuadorian Amazon, controlling for fish consumption, occupation, source of water and socio-demographic characteristics. METHODS: Analyze mercury levels in urine samples using cold vapour atomic fluorescence spectrometry from 76 indigenous men and women in eight riverine communities situated near oil wells or pipelines. Subjects answered a questionnaire soliciting socio-demographic, occupational and dietary information. Data were analyzed using multiple linear regression modeling. RESULTS: The mean value of U-Hg was 2.61µg/g creatinine (95% CI: 2.14-3.08), with 7% of the sample recording values above the global background standard suggested by The World Health Organization (5µg/g creatinine). Women who used water from a surface source had two and a half times the amount of mercury in their urine (mean=3.70µg/g creatinine, 95% CI: 2.26-5.15) compared with women who used other water sources (mean =1.39µg/g creatinine, 95% CI: 0.51-2.25). Men who were involved in an oil clean-up operation had twice as much mercury in their urine (mean =3.07µg/g creatinine, 95% CI: 1.97-4.16) as did those who worked on other tasks (mean =1.56µg/g creatinine, 95% CI: 1.48-2.65). Mercury levels were not associated with the number of fish meals per week. CONCLUSIONS: Indigenous peoples of the Peruvian and Ecuadorian Amazon living near oil production sites generally had urine mercury levels within the global background standard suggested by the World Health Organization. Increased levels of mercury in urine were detected for men involved in oil spill remediation and for women who relied on surface water for household needs. These findings signal the need for strict safety measures to limit the amount of oil entering the waterways in Andean Amazonia so as to protect the health of indigenous people.