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1.
Regul Toxicol Pharmacol ; 139: 105356, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36758784

RESUMEN

A fully integrated Chemicals Strategy for Sustainability (CSS) in respect of chemicals is crucial and must include: • An objective evaluation of the present situation including impacts of 'chemicals of concern' throughout their life cycle, that incorporates sustainability issues. • A framework that facilitates innovation of chemistry-based approaches to tackle each of the key sustainability issues. The EU CSS only addresses adverse impacts and mainly focusses on one aspect of risk assessment, the hazard to humans from individual industrial chemicals. The proposal removes consideration of the nature and amount of exposure, which is a critical determinant of risk. It can be presumed that this is solely to simplify, and hence speed up, regulatory decisions thereby enabling more chemicals to be assessed. The linkage of this proposed approach to address any of the major sustainability issues, such as environmental pollutants is obscure. For example, the well-recognised environmental problems caused by polymers such as plastics are not considered. The proposed change in the assessment methodology lacks any scientific justification and fails to address the sustainability issues the EU and the rest of the world are facing. The authors critically discuss a comprehensive innovative evaluation methodology for the impact of chemicals.


Asunto(s)
Contaminantes Ambientales , Humanos , Medición de Riesgo
3.
Environ Toxicol Chem ; 37(6): 1579-1593, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29352727

RESUMEN

The target lipid model (TLM) has been previously applied to predict the aquatic toxicity of hydrocarbons and other nonionic organic chemicals and for deriving the concentrations above which 95% of species should be protected (HC5 values). Several concerns have been identified with the TLM-derived HC5 when it is applied in a substance risk assessment context. These shortcomings were addressed by expanding the acute and chronic toxicity databases to include more diverse taxonomic groups and increase the number of species. The TLM was recalibrated with these expanded databases, resulting in critical target lipid body burdens and acute-to-chronic ratios that met the required guidelines for using species sensitivity distributions in substance risk assessment. The HC5 equation was further revised to consider covarying model parameters. The calculated HC5 values derived from the revised TLM framework were validated using an independent data set for hydrocarbons comprising 106 chronic values across plants, invertebrates, and fish. Assuming a sum binomial distribution, the 95% confidence limit for a 5% failure is between 0.8 and 9.2%. Eight chronic values fell below the HC5, corresponding to an excursion of 7.5%, which falls within the expected uncertainty bounds. Thus, calculated HC5s derived from the revised TLM framework were found to be consistent with the intended protection goals. Environ Toxicol Chem 2018;37:1579-1593. © 2018 SETAC.


Asunto(s)
Lípidos/análisis , Compuestos Orgánicos/toxicidad , Contaminantes Químicos del Agua/toxicidad , Animales , Carga Corporal (Radioterapia) , Bases de Datos de Compuestos Químicos , Peces , Hidrocarburos/toxicidad , Invertebrados/química , Invertebrados/efectos de los fármacos , Plantas/química , Plantas/efectos de los fármacos , Medición de Riesgo/métodos , Especificidad de la Especie , Pruebas de Toxicidad Aguda , Pruebas de Toxicidad Crónica
4.
Environ Toxicol Chem ; 35(12): 2948-2957, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27152493

RESUMEN

Because of the large number of possible aromatic hydrocarbon structures, predictive toxicity models are needed to support substance hazard and risk assessments. Calibration and evaluation of such models requires toxicity data with well-defined exposures. The present study has applied a passive dosing method to generate reliable chronic effects data for 8 polycyclic aromatic hydrocarbons (PAHs) on the green algae Pseudokirchneriella subcapitata and the crustacean Ceriodaphnia dubia. The observed toxicity of these substances on algal growth rate and neonate production were then compared with available literature toxicity data for these species, as well as target lipid model and chemical activity-based model predictions. The use of passive dosing provided well-controlled exposures that yielded more consistent data sets than attained by past literature studies. Results from the present study, which were designed to exclude the complicating influence of ultraviolet light, were found to be well described by both target lipid model and chemical activity effect models. The present study also found that the lack of chronic effects for high molecular weight PAHs was consistent with the limited chemical activity that could be achieved for these compounds in the aqueous test media. Findings from this analysis highlight that variability in past literature toxicity data for PAHs may be complicated by both poorly controlled exposures and photochemical processes that can modulate both exposure and toxicity. Environ Toxicol Chem 2016;35:2948-2957. © 2016 SETAC.


Asunto(s)
Chlorophyta/efectos de los fármacos , Cladóceros/efectos de los fármacos , Hidrocarburos Policíclicos Aromáticos/toxicidad , Contaminantes Químicos del Agua/toxicidad , Animales , Chlorophyta/crecimiento & desarrollo , Cladóceros/crecimiento & desarrollo , Cromatografía de Gases y Espectrometría de Masas , Hidrocarburos Policíclicos Aromáticos/análisis , Hidrocarburos Policíclicos Aromáticos/aislamiento & purificación , Microextracción en Fase Sólida , Pruebas de Toxicidad , Rayos Ultravioleta , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/aislamiento & purificación
5.
Integr Environ Assess Manag ; 11(4): 653-65, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25810150

RESUMEN

The trend in discharges of petroleum-related substances from refineries in Europe shows a consistent picture of declining emissions, since first measured in 1969. This decline coincides with enhanced internal capture or recycling procedures and increasing use of physical and biological treatments. At the same time, and partly in response to legislative drivers, there has been an increase in the use of chronic (long-term) toxicity tests and alternative methods for assessing the quality of effluent discharges. The Whole Effluent Assessment (WEA) approach has also driven the increased conduct of studies addressing the fate of effluent constituents. Such studies have included the use of biodegradation and solid-phase micro-extraction-biomimetic extraction (SPME-BE) methods to address potentially bioaccumulative substances (PBS). In this way, it is then possible to address the persistence and toxicity of these PBS constituents of an effluent. The data collected in various case studies highlights the advantages and pitfalls of using biologically-based methods to assess the potential for refinery effluents to cause environmental impacts.


Asunto(s)
Monitoreo del Ambiente/métodos , Residuos Industriales/análisis , Industria del Petróleo y Gas , Aguas Residuales/análisis , Eliminación de Residuos Líquidos , Aguas Residuales/estadística & datos numéricos , Contaminantes Químicos del Agua/análisis
6.
Environ Toxicol Chem ; 33(12): 2679-87, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25195918

RESUMEN

Substance risk assessments require estimation of predicted no-effect concentrations (PNECs) in soil and sediment. The present study applies the target lipid model (TLM) and equilibrium partitioning (EqP) model to toxicity data to evaluate the extrapolation of the TLM-derived aquatic PNECs to these compartments. This extrapolation assumes that the sensitivity of aquatic species is similar to that of terrestrial and benthic species. The acute species sensitivity distribution, expressed in terms of species-specific critical target lipid body burdens, was computed using the TLM-EqP framework and found to span a similar range as the aquatic organism species sensitivity distribution but with a slightly lower median value (less than 2 times). The species sensitivity distribution for acute-to-chronic ratios also exhibited a similar range and distribution across species, suggesting similar mechanisms of action. This hypothesis was further tested by comparing empirical soil/sediment chronic effect levels to the calculated PNEC derived using TLM-EqP. The results showed that 95% of the compiled chronic effects data fell above the PNEC, confirming an adequate protection level. These findings support the conclusion that TLM-derived aquatic PNECs can be successfully extrapolated to derive credible PNECs for soil and sediment compartments.


Asunto(s)
Sedimentos Geológicos/química , Modelos Teóricos , Suelo/química , Envejecimiento , Animales , Organismos Acuáticos/química , Organismos Acuáticos/efectos de los fármacos , Organismos Acuáticos/metabolismo , Disponibilidad Biológica , Carga Corporal (Radioterapia) , Compuestos Orgánicos/química , Compuestos Orgánicos/metabolismo , Compuestos Orgánicos/toxicidad
7.
Integr Environ Assess Manag ; 10(3): 437-48, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24687890

RESUMEN

PETRORISK is a modeling framework used to evaluate environmental risk of petroleum substances and human exposure through these routes due to emissions under typical use conditions as required by the European regulation for the Registration, Evaluation, Authorization and Restriction of Chemicals (REACH). Petroleum substances are often complex substances comprised of hundreds to thousands of individual hydrocarbons. The physicochemical, fate, and effects properties of the individual constituents within a petroleum substance can vary over several orders of magnitude, complicating risk assessment. PETRORISK combines the risk assessment strategies used on single chemicals with the hydrocarbon block approach to model complex substances. Blocks are usually defined by available analytical characterization data on substances that are expressed in terms of mass fractions for different structural chemical classes that are specified as a function of C number or boiling point range. The physicochemical and degradation properties of the blocks are determined by the properties of representative constituents in that block. Emissions and predicted exposure concentrations (PEC) are then modeled using mass-weighted individual representative constituents. Overall risk for various environmental compartments at the regional and local level is evaluated by comparing the PECs for individual representative constituents to corresponding predicted no-effect concentrations (PNEC) derived using the Target Lipid Model. Risks to human health are evaluated using the overall predicted human dose resulting from multimedia environmental exposure to a substance-specific derived no-effect level (DNEL). A case study is provided to illustrate how this modeling approach has been applied to assess the risks of kerosene manufacture and use as a fuel.


Asunto(s)
Contaminantes Ambientales/análisis , Contaminantes Ambientales/toxicidad , Modelos Teóricos , Petróleo/análisis , Petróleo/toxicidad , Animales , Exposición a Riesgos Ambientales/efectos adversos , Exposición a Riesgos Ambientales/análisis , Unión Europea , Regulación Gubernamental , Humanos , Nivel sin Efectos Adversos Observados , Medición de Riesgo/legislación & jurisprudencia , Medición de Riesgo/métodos
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