Proceedings of the third USA-USSR symposium on the effects of pollutants upon aquatic ecosystems.

3rd.

Proceedings of the third USA-USSR symposium on the effects of pollutants upon aquatic ecosystems.

1st & 2nd

A risk assessment for exposure to grunerite asbestos (amosite) in an iron ore mine

The potential for health risks to humans exposed to the asbestos minerals continues to be a public health concern. Although the production and use of the commercial amphibole asbestos minerals���grunerite (amosite) and riebeckite (crocidolite)���have been almost completely eliminated from world commerce, special opportunities for potentially significant exposures remain. Commercially viable deposits of grunerite asbestos are very rare, but it can occur as a gangue mineral in a limited part of a mine otherwise thought asbestos-free. This report describes such a situation, in which a very localized seam of grunerite asbestos was identified in an iron ore mine. The geological occurrence of the seam in the ore body is described, as well as the mineralogical character of the grunerite asbestos. The most relevant epidemiological studies of workers exposed to grunerite asbestos are used to gauge the hazards associated with the inhalation of this fibrous mineral. Both analytical transmission electron microscopy and phase-contrast optical microscopy were used to quantify the fibers present in the air during mining in the area with outcroppings of grunerite asbestos. Analytical transmission electron microscopy and continuous-scan x-ray diffraction were used to determine the type of asbestos fiber present. Knowing the level of the miner���s exposures, we carried out a risk assessment by using a model developed for the Environmental Protection Agency.

Avalia����o probabil��stica de riscos �� sa��de humana em ��rea contaminada�� por compostos�� organoclorados

Introdu����o: ��reas contaminadas por agentes qu��micos perigosos em regi��es urbanas representam riscos importantes �� sa��de humana e ao ambiente. Vila Carioca, localizada na cidade de S��o Paulo, �� uma ��rea contaminada por pesticidas organoclorados considerada cr��tica, pela magnitude da contamina����o, pela presen��a de pessoas residentes e pela complexidade de fontes da contamina����o. V��rios estudos de riscos j�� foram realizados por uma das empresas contaminadoras, no entanto, ainda h�� muita incerteza e controv��rsias sobre os riscos �� sa��de da popula����o. Objetivo: Avaliar o incremento de risco de c��ncer no tempo de vida para popula����o exposta por meio de uma avalia����o probabil��stica. M��todo: Foram utilizados dados secund��rios das contamina����es obtidos nos estudos de riscos efetuados pela empresa produtora de pesticidas organoclorados e tamb��m em documentos oficiais dos ��rg��os de sa��de e meio ambiente do Estado de S��o Paulo, resultantes do monitoramento da ��gua e do solo na ��rea residencial no per��odo de 1997 a 2012, para 335 subst��ncias. Foram selecionadas subst��ncias carcinog��nicas presentes na ��gua subterr��nea e solo com melhor conjunto de dados. Para a avalia����o probabil��stica foi empregado o m��todo de simula����o de Monte Carlo, por meio do software comercial ModelRisk. Foram utilizados os m��todos recomendados pela United States Environmental Protection Agency para a avalia����o de risco de exposi����o d��rmica e de incremento de riscos de c��ncer para subst��ncias mutag��nicas. Foram consideradas a ingest��o de ��gua e solo, e contato d��rmico com ��gua. Resultados: O incremento de risco de c��ncer no tempo de vida (IRLT) foi de 4,7x10-3 e 4,1x10-2 para o percentil 50% e 95%, respectivamente. As rotas de exposi����o mais importantes foram ingest��o e contato d��rmico com a ��gua subterr��nea, seguido da ingest��o de solo. O grupo et��rio que apresentou maior risco foi o das crian��as de 0 a 2 anos de idade. Conclus��o: Os riscos estimados s��o superiores aos valores considerados toler��veis. A avalia����o realizada foi conservativa, mas ressalta-se que a restri����o do uso da ��gua subterr��nea deve ser mantida e que a popula����o deve ser devidamente informada dos riscos envolvidos na ��rea, em especial, relacionados ao solo contaminado

Ocorr��ncia e caracteriza����o de Giardia e Cryptosporidium em ��guas captadas para abastecimento p��blico no munic��pio de Cajamar-SP e avalia����o do risco

Introdu����o: O risco �� sa��de humana ocasionado pela contamina����o biol��gica de ��guas captadas para abastecimento p��blico �� real��ado pela ocorr��ncia de surtos de doen��as associadas aos protozo��rios Giardia e Cryptosporidium, que possuem baixas doses infecciosas e alta capacidade de sobreviv��ncia no ambiente, al��m de serem capazes de resistir ao processo tradicional de desinfec����o da ��gua (clora����o). Partindo-se da hip��tese de que h�� um risco elevado de infec����o por estes protozo��rios pela ingest��o de ��gua tratada por m��todos convencionais e que fazem uso de mananciais superficiais impactados por contamina����o biol��gica, resultando num poss��vel incremento da incid��ncia de diarr��ias, este estudo se prop��s a verificar a ocorr��ncia destes protozo��rios em ��guas captadas para abastecimento p��blico no munic��pio de Cajamar-SP, caracterizar sua patogenicidade e avaliar o risco associado ao seu consumo atrav��s da ��gua tratada. M��todos: Foram coletadas 48 amostras do ribeir��o dos Cristais no ponto de capta����o da esta����o de tratamento de ��gua, semanalmente, durante 12 meses (de 16/05/2013 a 21/05/2014). A detec����o e a an��lise da concentra����o dos protozo��rios foram realizadas de acordo com M��todo 1623.1 da United States Environmental Protection Agency e a extra����o e caracteriza����o dos esp��cies/gen��tipos de Giardia e Cryptosporidium foi realizada atrav��s metodologias moleculares e seq��enciamento. O risco de infec����o pela ingest��o de cistos de Giardia e oocistos de Cryptosporidium presentes na ��gua tratada foi calculado usando a ferramenta da Avalia����o Quantitativa do Risco Microbiol��gico, a partir dos dados de concentra����o dos pat��genos obtidos pelo M��todo 1623.1, efici��ncia de remo����o dos (oo)cistos durante o processo convencional de tratamento da ��gua, modelo dose-resposta e taxa de ingest��o di��ria de ��gua para indiv��duos menores de 5 anos e maiores de 21 anos. Resultados: Cistos de Giardia foram detectados em 83,3% das amostras (40/48), com concentra����es variando desde o limite de detec����o (<0,1) at�� 8,6 cistos/L. Oocistos de Cryptosporidium foram etectados em 37,5% das amostras (18/48), com concentra����es variando desde o limite de detec����o (<0,1) at�� 2 oocistos/L. As esp��cies/gen��tipos encontrados (Giardia intestinalis A e B e Cryptosporidium parvum e hominis) s��o caracter��sticos de contamina����o antr��pica e s��o frequentemente identificados em estudos epidemiol��gicos como respons��veis por surtos. A estimativa do risco anual de infec����o por Giardia foi de 3,3x10-3 (IC95% 4,6x10-3) para crian��as e de 11,5x10-3 (IC95% 13,3x10-3) para adultos, enquanto o risco por Cryptosporidium foi de 1,1x10-3 (IC95% 1,7x10-3) para crian��as e de 3,9x10-3 (IC95% 5,0x10-3) para adultos. O incremento da incid��ncia de diarr��ias foi observado no cen��rio de estudo ap��s um acidente que resultou em transbordamento de esgotos n��o tratados no manancial, coincidindo com o aumento na detec����o de (oo)cistos. Conclus��o: Os resultados evidenciaram que a vulnerabilidade do ribeir��o dos Cristais a contamina����es biol��gicas pode culminar em um risco elevado de infec����o e adoecimento por Giardia e Cryptosporidium atrav��s da ingest��o de ��gua tratada. Portanto, o caso �� preocupante, tanto do ponto de vista do tratamento e abastecimento de ��gua pot��vel, quanto da degrada����o e contamina����o do manancial, evidenciando a necessidade de se estabelecer medidas de interven����o direcionadas a promover a qualidade da ��gua e garantir sua seguran��a

Fish Consumption and Prenatal Mercury Exposure

Methyl mercury levels in fish tissues have recently become a health issue. Does this toxin adversely affect humans to the point that fish consumption should be severely limited? Health effects of high levels of mercury exposure to human adults are fairly well known, however the effects of lower levels of exposure on human fetal development are less understood. Recent guidelines issued by the United States Food and Drug Agency and the Environmental Protection Agency recommended that pregnant women should refrain from consuming some types of fish, and limit consumption to certain levels, but results of health studies used to develop recommendations were inconclusive when low levels of in-utero methyl mercury exposure were compared. Other studies demonstrated health benefits of fish consumption to developing fetuses. These health benefits may be an over-riding factor, and my interpretation of various studies concludes that restricted consumption of some fish species may be premature at this time due to a need to balance potential health benefits against mercury toxicity hazard.

PCDD/F Emissions from Light-Duty Diesel Vehicles Operated under Highway Conditions and a Diesel-Engine Based Power Generator

PCDD/F emissions from three light-duty diesel vehicles���two vans and a passenger car���have been measured in on-road conditions. We propose a new methodology for small vehicles: a sample of exhaust gas is collected by means of equipment based on United States Environmental Protection Agency (U.S. EPA) method 23A for stationary stack emissions. The concentrations of O2, CO, CO2, NO, NO2 and SO2 have also been measured. Six tests were carried out at 90-100 km/h on a route 100 km long. Two additional tests were done during the first 10 minutes and the following 60 minutes of the run to assess the effect of the engine temperature on PCDD/F emissions. The emission factors obtained for the vans varied from 1800 to 8400 pg I-TEQ/Nm3 for a 2004 model year van and 490-580 pg I-TEQ/Nm3 for a 2006 model year van. Regarding the passenger car, one run was done in the presence of a catalyst and another without, obtaining emission factors (330-880 pg I-TEQ/Nm3) comparable to those of the modern van. Two other tests were carried out on a power generator leading to emission factors ranging from 31 to 78 pg I-TEQ/Nm3. All the results are discussed and compared with literature.

Quaternary ammonium-functionalized silica sorbents for the solid-phase extraction of aromatic amines under normal phase conditions

Quaternary ammonium-functionalized silica materials were synthesized and applied for solid-phase extraction (SPE) of aromatic amines, which are classified as priority pollutants by US Environmental Protection Agency. Hexamethylenetetramine used for silica surface modification for the first time was employed as SPE sorbent under normal phase conditions. Hexaminium-functionalized silica demonstrated excellent extraction efficiencies for o-toluidine, 4-ethylaniline and quinoline (recoveries 101���107%), while for N,N-dimethylaniline and N-isopropylaniline recoveries were from low to moderate (14���46%). In addition, the suitability of 1-alkyl-3-(propyl-3-sulfonate) imidazolium-functionalized silica as SPE sorbent was tested under normal phase conditions. The recoveries achieved for the five aromatic amines ranged from 89 to 99%. The stability of the sorbent was evaluated during and after 150 extractions. Coefficients of variation between 4.5 and 10.2% proved a high stability of the synthesized sorbent. Elution was carried out using acetonitrile in the case of hexaminium-functionalized silica and water for 1-alkyl-3-(propyl-3-sulfonate) imidazolium-functionalized silica sorbent. After the extraction the analytes were separated and detected by liquid chromatography ultraviolet detection (LC-UV). The retention mechanism of the materials was primarily based on polar hydrogen bonding and ������� interactions. Comparison made with activated silica proved the quaternary ammonium-functionalized materials to offer different selectivity and better extraction efficiencies for aromatic amines. Finally, 1-alkyl-3-(propyl-3-sulfonate) imidazolium-functionalized silica sorbent was successfully tested for the extraction of wastewater and soil samples.

Screen-printed electrode based electrochemical detector coupled with ionic liquid dispersive liquid���liquid microextraction and microvolume back-extraction for determination of mercury in water samples

A novel approach is presented, whereby gold nanostructured screen-printed carbon electrodes (SPCnAuEs) are combined with in-situ ionic liquid formation dispersive liquid���liquid microextraction (in-situ IL-DLLME) and microvolume back-extraction for the determination of mercury in water samples. In-situ IL-DLLME is based on a simple metathesis reaction between a water-miscible IL and a salt to form a water-immiscible IL into sample solution. Mercury complex with ammonium pyrrolidinedithiocarbamate is extracted from sample solution into the water-immiscible IL formed in-situ. Then, an ultrasound-assisted procedure is employed to back-extract the mercury into 10 ��L of a 4 M HCl aqueous solution, which is finally analyzed using SPCnAuEs. Sample preparation methodology was optimized using a multivariate optimization strategy. Under optimized conditions, a linear range between 0.5 and 10 ��g L���1 was obtained with a correlation coefficient of 0.997 for six calibration points. The limit of detection obtained was 0.2 ��g L���1, which is lower than the threshold value established by the Environmental Protection Agency and European Union (i.e., 2 ��g L���1 and 1 ��g L���1, respectively). The repeatability of the proposed method was evaluated at two different spiking levels (3 and 10 ��g L���1) and a coefficient of variation of 13% was obtained in both cases. The performance of the proposed methodology was evaluated in real-world water samples including tap water, bottled water, river water and industrial wastewater. Relative recoveries between 95% and 108% were obtained.

Semivolatile and Volatile Compound Evolution during Pyrolysis and Combustion of Colombian Coffee Husk

Thermal characterization of coffee husk (Coffea arabica) from Colombian coffee has been studied. Different products, mostly volatile and semivolatile compounds, were analyzed, paying special attention to 16 polycyclic aromatic hydrocarbons (PAHs) classified by the United States Environmental Protection Agency (U.S. EPA) as priority pollutants, frequently used for checking toxicity in environmental samples. A fixed amount of raw material was exposed to different excess air ratios (�� = 0���2.33) and nominal temperature of 1123 K in a horizontal quartz reactor. The results show that coffee husk is a promising biomass for energetic exploitation with reduced formation of PAHs in a low air excess ratio. This implies reduction of carcinogenic potential in the limited presence of oxygen, demonstrated by calculating the carcinogenic potential (KE) for each experimental condition. Most volatile and semivolatile compounds followed different trends, with the oxygen presence prevailing their decomposition with increasing the air excess ratio.

Greater TTIP Ambition in Chemicals: Why and how. CEPS Special Report, 28 July 2015. Paper No. 10 in the CEPS-CTR project ���TTIP in the Balance��� and CEPS Special Report No. 114/July 2015.

To date, the negotiations over chemicals in the Translatlantic Trade and Investment Partnership (TTIP) have not shown sufficient ambition. The talks have focused too much on the differences in the two ���systems���, rather than on the actual levels of health and environmental protection for substances regulated by both the US and the EU. Given the accomplishments within the OECD and the UN Globally Harmonised System of Classification and Labelling of Chemicals (GHS), the question is whether TTIP can be any more ambitious in the area of chemicals? We find that there is no detailed or systematic knowledge about how the two levels of protection in chemicals compare, although caricatures and stereotypes abound. This is partly due to an obsessive focus on a single US federal law, the Toxic Subtances Control Act (TSCA), whereas in practice US protection depends on many statutes and regulations, as well as on voluntary withdrawals (under pressure from the Environmental Protection Agency) and severe common law liability. This paper makes the economic case for firmly addressing the regulatory barriers, discusses the EU���s proposals, finds that the European Parliament���s Resolution on TTIP of July 2015 lacks a rationale (for chemicals), argues that both TSCA and REACH ought to be improved (based on ���better regulation���), discusses the link with a global regime, advocates significant improvement of market access where equivalence of health and environmental objectives is agreed and, finally, proposes to lower the costs for companies selling in both markets by allowing them to opt into the other party���s more stringent rules, thereby avoiding duplication while racing-to-the-top. The ���living agreement��� on chemicals ought to be led by a new TTIP institution authorised to establish the level of health and environmental protection on both sides of the Atlantic for substances regulated on both sides. These findings will lay the foundation for a highly beneficial lowering of trading costs without in any way affecting the level of protection. Indeed, this is exactly what TTIP is, or should be, all about.This paper is the 10th in a series produced in the context of the ���TTIP in the Balance��� project, jointly organised by CEPS and the Center for Transatlantic Relations (CTR) in Washington, D.C. It is published simultaneously on the CEPS (www.ceps.eu) and CTR websites (http://transatlantic.sais-jhu.edu).