In October 2013 the Swedish Environmental Research Institute IVL were assigned by the Swedish EPA to make an assessment of the need for further follow-up of Swedish national screening studies performed during the years 2007-2012. Defined tasks were to:
Select approximately 25 substances for risk evaluation and to identity if there is a need for a more in-depth evaluation for any of these substances.
Select approximately 8 screening studies where there are needs for follow-up studies and rank them in order of preference. The need for method development should also be identified.
Forty screening studies were performed during the selected time period and the total number of screened substances amounted to 540 individual chemical substances, groups of substances and metals (Appendix 1, Table 1). For the Swedish EPA it was important that each step in the selection procedure was accounted for in the report.
The first set criteria for reduction of substances not relevant for
risk evaluation were:
Classical well known substances (e.g. PCBs, dioxins, metals) or are metabolites.
Substances with low detection frequency in biotic samples including humans, < 50%.
Priority substances within the Water Framework Directive (WFD) and therefore considered as well known
Substances that should be treated as a group rather than as individual compounds,
e.g. unintentionally produced substances.
After this selection step, 22 substances remained on the list (Table 3). Two brominated flame retardants (HBB and PBEB), two UV-filters (OTNE and AC) and one benzotriazole (UV 327) was suggested for an in depth evaluation.
The forty screening studies were evaluated for follow up (Table 2). The set of criteria for studies not selected for a follow-up were:
A follow up study has already been performed (7 studies).
The screening study concerned priority substances within the WFD (2 studies).
The screening showed that the substances do not pose any risk or that no issues remain at present (5 studies).
Follow-up studies, research projects and/or literature reviews are ongoing (9 studies).
Method development is ongoing or needed before further screening (2 studies).
Evaluation of Swedish National Screening Studies 2007-2012 IVL report B2159 Assement of the Need for Follow-up
Six studies were not prioritized for a new screening but needs to be considered (see Appendix 3, Table 1 for comments). Finally, nine studies, of which two concerns fragrances, where prioritized for further screening.
Below the screening studies are listed and commented in priority order where the first three are of most relevance. (See the report for each screening study for a more extended presentation.)
National screening, 2009, UV filters
The screening results show that the occurrence of UV-filters is widespread in surface water from background areas and in the urban environment. Several of the included UV-filters pose a potential risk to the environment. The highest concentrations occur during the reproductive season and the use is not likely to decrease. The industry of personal care products may be perceptive to new information on risks concerning these substances. A new screening should therefore be preceded by a review on use, ecotoxicity and persistence of UV filters.
National screening, 2010, Pharmaceuticals
There is an increasing amount of evidence that pharmaceuticals may cause effects in the environment. Three pharmaceutical substances are on the watch-list within the WFD. Thus, more data is requested concerning environmental concentrations. The results in the screening show that removal rates of some pharmaceuticals in WWTP are difficult to determine. Method development and a follow-up screening would contribute to a better assessment of predicted environmental concentrations. Furthermore, the knowledge of the fate of pharmaceuticals in sewage sludge, in soil receiving sludge amendments and subsequent uptake in biota is limited. In a recent screening conducted in Norway the authors highlighted the number of pharmaceuticals detected in prawns, fish and birds (> 30; Miljødirektoratet 2013).
National screening, 2008, Musk substances and metabolites
National screening, 2011 Fragances; OTNE, acetyl cedrene and diphenyleter
Fragrance substances and their metabolites are widespread in the environment and were detected in surface water, sediment, fish, soil (to which sludge has been amended) and in breast milk. Many of these substances can bioaccumlate and the data indicate that these substances are persistent and that atmospheric long range transport occurs. Ecotoxicological data are limited for many of these substances. A new screening should be preceded by a literature review regarding usage and relevant substances. Fragrances that have been reported to occur in human samples should be included, and screening in human breast milk repeated. Furthermore, we suggest that the air compartment should be included.
National screening, 2011 Benzothiazoles, benzenediamines, dicyclohexylamine and benzotriazoles
A widespread occurrence of benzotriazoles was reported, both at background and urban areas. However, as no ecotoxicity data were found, no assessment of risk could be made.
The result of the screening was also reflected by analytical challenges of these substances. Benzothiazoles and benzotriazoles have recently been reported in different matrixes in a non-target screening in Norway (Miljødirektoratet, 2013).
A follow up screening is recommended, but before the need for method development should be assessed.
National screening, 2007, Platinum group metals
The screening study included the platinum group elements (PGEs) platinum (Pt), palladium (Pd) and rhodium (Rh). Pd was almost consistently detected in the biological samples (fish, moose, cow, white tailed eagle and plants). The concentrations of Pd in groundwater were higher than in run-off water ponds. The authors concluded that the results in this study do not indicate that PGEs pose a risk to humans or the aquatic ecosystem, but that this conclusion is based on lack of reference values and proper risk assessments for humans as well as biota.
National screening, 2007, Organophosphate esters in human breast milk and fish in Swedish lakes and coastal areas
The results from this study indicate that environmental load of organophosphate esters (OP) are high and that there is chronic exposure of OP. The authors concluded that the knowledge of the effects and the fate of these substances is limited and that more information on sources, degradation and uptake in biota is needed. A literature survey is suggested before decision on the selection of substances and environmental matrices for a follow up. Air and dust are likely to be important exposure routes for humans.
National screening, 2008, Exposure and effect screening in urine of women
The results show that urine is a good matrix for human biomonitoring of many organic chemicals and metals. The authors suggested follow-up studies on a selection of PAHs and phthalate metabolites and a larger test group could better establish factors influencing metabolite concentration in urine. We suggest that based on the outcome of other screening studies, also metabolites of other organic chemicals and metals,
e.g. silver and metabolites of fragrances, should be considered.
National screening, 2007, Octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate
Available data for the aquatic environment indicates that octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate has low acute toxicity but no chronic tests have been done, and, thus, it is not possible to determine the risk. Given the persistent properties and the large production volume a follow up study is recommended, also including degradation products. It may be of interest to also include other antioxidants of similar chemical structure and their degradation products.