Time-trends of metals and organic contaminants in sewage sludge
2012 (English)In: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, Vol. 46, no 15, 4841-4851 p.Article in journal (Refereed) Published
The occurrence of chemicals in sludge from sewage treatment plants (STPs) is of concern for human health and the environment, especially since STPs are considered to be major secondary sources of many toxic chemicals into the environment. Land application of sewage sludge is an attractive option for sludge management, as it consists of nutrients and organic matter. However, before sludge can be used for this purpose, the content of hazardous substances needs to be reduced to levels considered safe. Legislations and regulations are put in place to minimize the release of harmful chemicals into the environment, e.g. via sewage sludge. Temporal trends analysis of sludge contaminants can be used to assess the effectiveness of such actions. Such analyses can be performed retrospectively, using sludge stored in environmental specimen banks, to investigate new or emerging environmental contaminants. The present study provides data from time-trend analyses of metals, persistent organic pollutants, pharmaceuticals, personal care products, and other organic compounds in sludge from Swedish STPs (based on seven years of measurements). The analysis showed that sludge is a suitable matrix for time-trend studies and it can take on average 12 years (range, 5-26 years) to track an annual change of ±10% (with a power of 80%). Statistically significant trends were found for 18 out of the 77 compounds subjected to analysis, of which 75% showed decreasing trends. Triclosan and the antibiotic norfloxacin followed the same trend as the national recorded usage and decreased annually by 65% and 60%, respectively. The opposite was true for the methylsiloxanes, which showed an annual average increase of about 30%. A downward trend (about 20% year−1) was observed for the polybrominated diphenylethers (PBDEs 154 and 183), while PBDE 209 increased by 16%. Further measurements are required to determine if the substitution of PBDEs by chlorinated paraffins or organophosphorus compounds have resulted in increased concentrations of the latter in sludge.
Place, publisher, year, edition, pages
Elsevier, 2012. Vol. 46, no 15, 4841-4851 p.
Emerging pollutants, Organotin compounds, Organophosphorus compounds, POP, PPCP
IdentifiersURN: urn:nbn:se:umu:diva-51312DOI: 10.1016/j.watres.2012.05.048OAI: oai:DiVA.org:umu-51312DiVA: diva2:478985