Nikolaos Voulvoulis

Aquatic environmental assessment of the top 25 English prescription pharmaceuticals

An environmental assessment is presented for the 25 most used pharmaceuticals in the National Health Service (NHS) in England in 2000. Predicted environmental concentrations (PECs) for the aquatic environment were calculated using conservative assumptions and all PECs exceeded 1 ng 1 (-1). The calculation of predicted no-effect concentration (PNEC) based on aquatic toxicity data from the literature was possible for eleven of the pharmaceuticals. PNECs were predicted with ECOSAR for 12 of the remaining 14 but no data was available for two of the compounds. The PEC/ PNEC ratio exceeded one for Paracetamol, Amoxycillin, Oxytetracycline and Mefenamic acid. Comparisons of the predicted concentrations of the compounds in sewage sludge based on either calculated sludge-water coefficients (Kd), octanol water coefficients (K(ow)), acid base constants (pKa) or environmental modelling revealed large variations. No toxicity data was available for the terrestrial environment and no assessment was made.

Human Pharmaceuticals in the Aquatic Environment a Review

There has been increasing concern in recent years about the occurrence, fate and toxicity of pharmaceutical products in the aquatic environment. Many of the more commonly used drug groups (for example antibiotics) are used in quantities similar to those of pesticides and other organic micropollutants, but they are not required to undergo the same level of testing for possible environmental effects. The full extent and consequences of the presence of these compounds in the environment are therefore largely unknown and the issue as a whole is ill-defined. Although these compounds have been detected in a wide variety of environmental samples including sewage effluent, surface waters, groundwater and drinking water, their concentrations generally range from the low ppt to ppb levels. It is therefore often thought to be unlikely that pharmaceuticals will have a detrimental effect on the environment. However, the lack of validated analytical methods, limited monitoring data and the lack of information about the fate and toxicity of these compounds and/or their metabolites in the aquatic environment makes accurate risk assessments difficult.

Human Pharmaceuticals in Wastewater Treatment Processes

The presence of human pharmaceutical compounds in surface waters is an emerging issue in environmental science. In this study the occurrence and behavior of human pharmaceuticals in a variety of wastewater treatment processes is reviewed. Although some groups are not affected by sewage treatment processes others are amenable to degradation, albeit incomplete. While water purification techniques such as granular activated carbon could potentially remove these pollutants from wastewater streams, the high cost involved suggests that more attention should be given to the potential for the optimization of current treatment processes, and reduction at source in order to reduce environmental contamination.

Household disposal of pharmaceuticals as a pathway for aquatic contamination in the United kingdom.

Pharmaceuticals are produced and used in increasingly large volumes every year. With this growth comes concern about the fate and effects of these compounds in the environment. The discovery of pharmaceuticals in the aquatic environment has stimulated research in the last decade. A wide range of pharmaceuticals has been found in fresh and marine waters, and it has recently been shown that even in small quantities, some of these compounds have the potential to cause harm to aquatic life. The primary pathway into the environment is the use and disposal of medicines; although much of the research in the area currently focuses on the removal of pharmaceuticals during sewage treatment processes, disposal via household waste might be a significant pathway requiring further research. To investigate the household disposal of unused and expired pharmaceuticals as a source of pharmaceutical compounds in the environment, we carried out a survey and interviewed members of 400 households, predominantly from southeastern England. We used the information on when and how they disposed of unfinished pharmaceuticals to construct a conceptual model to assess the pathways of human pharmaceuticals into the environment. The model demonstrated that disposal of unused pharmaceuticals, either by household waste or via the sink or toilet, may be a prominent route that requires greater attention.

Alternative antifouling biocides

In response to increasing scientific evidence on the toxicity and occurrence of organotin residues from antifouling paints in the aquatic environment, the use of triorganotin antifouling products was banned on boats of less than 25 m length in many countries during 1987. The use of tributyltin (TBT) products on small boats was superseded by products based on copper, containing organic booster biocides to improve the efficacy of the formulation. Available information and evidence on the occurrence, fate and toxicity of these biocides is reviewed. It is concluded that increased copper concentrations in the aquatic environment, due to the increased use of copper-based antifoulants, do not have significant effects on marine ecosystems. However, lack of validated analytical methods, limited monitoring data, and very little information about the fate and toxicity of the booster biocides in the aquatic environment, make accurate risk assessments in relation to these compounds difficult. Copyright

Potential Ecological and Human Health Risks Associated With the Presence of Pharmaceutically Active Compounds in the Aquatic Environment

ABSTRACT Recently, considerable interest has developed regarding the presence of pharmaceuticals in the environment, but as yet the potential ecological effects associated with the presence of these compounds have been largely ignored. In this review, laboratory-based acute and chronic toxicity data, as well as studies concerned with the effects of pharmaceuticals on a variety of different organisms, are examined, along with the reported environmental concentrations of pharmaceuticals in aquatic systems. The possible sources and pathways of these compounds to the environment and the effects of a variety of medicines on a range of organisms are also highlighted, and recommendations are made for further research.

Cadmium levels in Europe: implications for human health

In this study we used the Forum of European Geological Surveys geochemical baseline data to examine the distribution of cadmium (Cd) in Europe, with a particular reference to the international soil and water guideline values. The highest cadmium levels were found to occur in topsoil and to follow closely the distribution of P2O5, suggesting that the contamination was from the use of rock phosphate fertilizer in intensive arable agriculture. In terms of human health impacts, food (up to several hundred μg/day) was found as the only major route of exposure to Cd for the non-smoking general population. It appeared that low levels of chronic exposure to Cd resulted in completely different human health impacts than those high levels that had caused the ‘itai–itai’ disease. Some correlations were suggested between cadmium levels and the age-adjusted prostate or breast cancer rates distributed in the European countries under study.

Arsenic and selenium

This chapter outlines the main effects of arsenic and selenium on human and animal health, their abundance and distribution in the environment, sampling and analysis, and the main factors controlling their speciation and cycling. Such information should help identify aquifers, water resources and soils at risk from high concentrations of arsenic and selenium, and areas of selenium deficiency. Human activity has had, and is likely to continue to have, a major role in releasing arsenic and selenium from the geosphere and in perturbing the natural distribution of these and other elements over the Earths surface.

Occurrence of Four Biocides Utilized in Antifouling Paints, as Alternatives to Organotin Compounds, in Waters and Sediments of a Commercial Estuary in the UK

Waters and sediments from marinas, mooring areas and coastal sites in the Blackwater Estuary, Essex, UK were collected and analysed for the occurrence of Irgarol 1051, chlorothalonil, dichlofluanid and diuron. These biocides were introduced as alternatives to organotin compounds in antifouling products, after restrictions imposed on the use of tributyltin (TBT) in 1987. Samples were collected at the end of one boating season (October 98) and the beginning of the following one (June 99). An input survey was also undertaken with the objective of identifying input sources of these biocides and quantifying the amounts used in the catchment area. The results of the monitoring exercise exhibited some agreement with the findings of the input survey. Irgarol, dichlofluanid and chlorothalonil were detected at a number of sites. Concentrations of Irgarol and dichlofluanid in waters and sediments were enhanced after the boating season and the highest ones were relatively enhanced within the marinas, implying that use in antifoulants accounted for the inputs. Contamination with chlorothalonil was more widespread, consistent with its use in agriculture.

Comparative environmental assessment of biocides used in antifouling paints.

In response to increasing scientific evidence on the toxicity and persistence of organotin residues from antifouling paints in the aquatic environment, the use of triorganotin antifouling products was banned on boats of less than 25 m length in many countries during 1987. Alternatives to tributyltin (TBT) paint are mainly copper based coatings containing organic booster biocides to improve the efficacy of the formulation, and have been utilised on small boats for the last 10 years. With policies encouraging a total ban on TBT, it is expected that these biocides will be used to a greater extent in the future. Limited data and information are available on the environmental occurrence, fate, toxicity, and persistence of these biocides, and thus any decisions on policies regulating antifoulants cannot be fully informed. In this study, a multicriteria comparison of alternative biocides, based on a general assessment of available information in the literature, provided support for the use of the precautionary principle with respect to policies on antifouling products. This assessment was validated by a more detailed comparison of four selected biocides and TBT. Results indicate that TCMS pyridine and TCMTB demonstrate environmental characteristics similar to TBT and thus detail risk assessments are needed before their use is permitted. The widespread use of the other biocides should be allowed only after research to fill the gaps in knowledge with respect to their toxicity and persistence in aquatic environments.