title: The contribution of household chemicals to environmental discharges via effluents: combining chemical and behavioural data.
abstract: Increased concentrations and loads of soluble, bioavailable forms of phosphorus (P) are a major cause of eutrophication in streams, rivers and lakes in many countries around the world. To implement P control measures, it is essential to identify P sources and their relative load contributions. A proportion of P loading generated from household wastewaters is derived from detergents yet the P compositions of the range of domestic detergents and their usage is poorly understood. To quantify P loads from household detergents, we analysed a large range of detergents and cleaning products commonly available in the UK and Europe, comparing regular and eco-labelled products. Chemical data were coupled with survey results on typical household detergents preferences and usage (n = 95 households). We also determined whether the major and trace element signatures of these household detergents could potentially be used as anthropogenic tracers in watercourses. The greatest P concentrations were found for regular dishwasher detergents (43-131 mg P/g detergent) whilst the range of P in eco-labelled dishwasher detergents was much lower (0.7-9.1 mg P/g detergent). Other household cleaning groups contained relatively smaller P concentrations. Considering the survey results, detergents' total P loading generated from one household using either regular or eco labelled products, was 0.414 and 0.021 kg P/year, respectively. Given a household occupancy of 2.7, the P load from all detergent use combined was 0.154 kg P/person/year of which the dishwasher contribution was 0.147 kg P/person/year. In terms of elemental signatures, (DWD) dishwasher detergents were significantly (P-value <0.001) different from other household cleaning products in their As, Na, TP, Si, Sr, SRP, Ti, Zn and Zr signatures. Na, P and B were all positively correlated with each other, indicating their potential use as a tracer suite for septic tank effluent in combination with other indices. We conclude that forthcoming legislation for reducing P contents in domestic laundry detergents will not address the dominant environmental P load from DWD and studies such as this are important in promoting and allowing scenarios of benefits from future legislation for DWD.
authors.affiliation: The James Hutton Institute, Craigiebuckler, Aberdeen AB15 8QH, Scotland, UK. Electronic address: samia.richards@hutton.ac.uk.
authors.forename: Samia
authors.initials: S
authors.lastname: Richards
authors.affiliation: The James Hutton Institute, Craigiebuckler, Aberdeen AB15 8QH, Scotland, UK.
authors.forename: Eric
authors.initials: E
authors.lastname: Paterson
authors.affiliation: Bangor University, Bangor, Gwynedd LL57 2UW, UK.
authors.forename: Paul J A
authors.initials: PJA
authors.lastname: Withers
authors.affiliation: The James Hutton Institute, Craigiebuckler, Aberdeen AB15 8QH, Scotland, UK.
authors.forename: Marc
authors.initials: M
authors.lastname: Stutter
mesh_terms: D003902:Detergents / Q000737:chemistry; D004323:Drainage, Sanitary / Q000706:statistics & numerical data; D004784:Environmental Monitoring; D005060:Europe; D005068:Eutrophication; D005191:Family Characteristics; D006801:Humans; D010758:Phosphorus / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry*; D014876:Water Pollution / Q000331:legislation & jurisprudence / Q000517:prevention & control
chemical_list: D003902:Detergents; D014874:Water Pollutants, Chemical; D010758:Phosphorus
keywords: Bioavailable P; Detergents P; Eutrophication; Tripolyphosphate; Wastewater; Zeolite A