Comparing aquatic risk assessment methods for the photosynthesis-inhibiting herbicides metribuzin and metamitron

Brock, T.C.M.; Crum, S.J.H.; Deneer, J.W.; Heimbach, Fred; Roijackers, R.M.M.; Sinkeldam, J.A.

doi:10.1016/j.envpol.2003.12.022

Cited by 48 publications

(58 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Generally, the exudation of organic material from algae to bacteria may, in fact, have a more pronounced role in the benthic system than in the microbial loop of the pelagic system (Goto et al 1999, Tobias et al 2003, particularly in microbial mats as thick as those in our experiment. In pelagic systems, toxicant impacts are often considered to be transferred from the lowest trophic level (algae) to higher trophic levels (Breitburg et al 1999, Bundy et al 2003, Brock et al 2004). In our benthic system, however, top-down effects may also have been important.…”

Section: Complex Interactive Effectsmentioning

confidence: 99%

Combined nutrienttoxicant effects on a shallow-water marine sediment system: sensitivity and resilience of ecosystem functions

Sundbäck¹,

Petersen²,

Dahllöf³

et al. 2007

Mar. Ecol. Prog. Ser.

View full text Add to dashboard Cite

Effects of nutrient status and short-term, low-level exposure to the antifouling biocide copper pyrithione (CPT) on intact shallow-water sediment were studied in an outdoor experiment, focusing on basic ecosystem functions driven by microorganisms. These functions were trophic status (autotrophy/heterotrophy), direction of dissolved inorganic nitrogen (DIN) flux, and the ratio of algal N assimilation:denitrification, and were based on measurements of daily sediment -water oxygen and nitrogen fluxes and denitrification. Bacterial production and biomass of microphytobenthos, meiofauna, and bacteria were also measured. The recovery of the functions was studied for 38 d. CPT exposure did not change basic ecosystem functions; the sediment remained autotrophic and a net sink of DIN, where microalgal N incorporation far exceeded denitrification. However, CPT affected individual N-cycling variables (ammonium flux, denitrification), as well as community respiration and bacterial production, with the direction of the response depending on sediment nutrient status. Significant CPT effects were more frequent in the nutrient-enriched sediment. Direct toxic effects were followed by indirect food-web-mediated (top-down) effects, leading to different timing and direction of effects with different sediment nutrient status. Permutational multivariate analysis of variance showed that initial CPT effects on system functions in both nutrient regimes were followed by an oscillating recovery process, where effects remained longer in the nutrient-enriched sediment. While single CPT exposure events may not affect general metabolic functions (oxygen flux) -at least not in net autotrophic sediments -repeated CPT exposure of sediment microbiota may impact nitrogen cycling in shallow, eutrophied waters.

show abstract

Section: Complex Interactive Effectsmentioning

confidence: 99%

Combined nutrienttoxicant effects on a shallow-water marine sediment system: sensitivity and resilience of ecosystem functions

Sundbäck¹,

Petersen²,

Dahllöf³

et al. 2007

Mar. Ecol. Prog. Ser.

View full text Add to dashboard Cite

show abstract

“…Summary of the hazardous concentrations to 5% of the species (HC5) and the lower limit of the 95% confidence interval (in parentheses) for the insecticide chlorpyrifos, the herbicide metribuzin, and the fungicide carbendazim The HC5 values were calculated on the basis of acute or chronic toxicity data for species belonging to the relevant, sensitive taxonomic group of aquatic organisms and to aquatic vertebrates. Most data were retrieved from Maltby et al (2005), Brock et al (2004) and Van Wijngaarden et al (1998). In addition, the lower part of the table presents the higher-tier predicted-no-effect concentrations in line with the Ecological Threshold Principle (Table 7) and Community Recovery Principle ( carbendazim, however, the 1st-tier triggers (Table 9) were somewhat higher than the EQS short-term , EQS long-term , and RAC short-term values based on the SSD approach (Table 10).…”

Section: ¼ Environmental Qualitymentioning

confidence: 99%

Aquatic Risks of Pesticides, Ecological Protection Goals, and Common Aims in European Union Legislation

Brock

Arts

Maltby

2006

Integr Environ Assess Manag

121

View full text Add to dashboard Cite

This discussion paper presents a framework for spatiotemporal differentiation in ecological protection goals to assess the risks of pesticides in surface waters. It also provides a proposal to harmonize the different scientific approaches for ecotoxicological effect assessment adopted in guidance documents that support different legislative directives in the European Union (Water Framework Directive and Uniform Principles). Decision schemes to derive maximum permissible concentrations in surface water are presented. These schemes are based on approaches recommended in regulatory guidance documents and are scientifically underpinned by critical review papers concerning the impact of pesticides on freshwater organisms and communities. Special attention is given to the approaches based on standard test species, species sensitivity distribution curves, and model ecosystem experiments. The decision schemes presented here may play a role in the ''acceptability'' debate and can be used as options in the process of communication between risk assessors and risk managers as well as between these risk experts and other stakeholders.

show abstract

“…These types of tests are difficult to extrapolate to natural field conditions since they exclude a large number of potential interactions that occur among the numerous components of complex natural ecosystems, so-called indirect effects (Brock et al 2004). This also implies that simple laboratory experiments ignore interactions between stressors that act simultaneously upon the system.…”

Section: Introductionmentioning

confidence: 99%

Combined effects of an antifouling biocide and nutrient status on a shallow-water microbenthic community

Larson

Petersen²,

Dahllöf

et al. 2007

Aquat. Microb. Ecol.

View full text Add to dashboard Cite

The complex systems of shallow-water sediments are today subjected to varying nutrient inputs combined with other anthropogenic stressors, such as toxicants. The effects of differences in nutrient status of the sediment combined with short-term, low-level exposure to the anti-fouling biocide copper pyrithione (CPT) were studied in a 38 d experiment using intact sediment in a flowthrough mesocosm system. Abundance and diversity of microphytobenthos, bacteria and meiofauna were assessed together with sediment -water oxygen and nutrient fluxes (day and night) and denitrification. More effects were found for the sediment with higher nutrient status, but these combined effects could not be predicted by adding the separate effects of nutrients and CPT observed for the sediment with low nutrient status. Biomass and diversity of microphytobenthos increased later on in the experiment due to CPT exposure, as did bacterial activity and abundance. CPT exposure also increased the proportion of nematodes in the meiofauna. Generally, prokaryotic functions appeared more affected by CPT exposure than eukaryotic. Differences in the response of functional variables suggest that eukaryotic photoautotrophs possess a higher functional redundancy than heterotrophs. Among nutrient fluxes the nitrogen cycling was affected through changed rates of ammonium flux and denitrification. The integrated analyses show a clearer effect of CPT on the community structure under low-nutrient status, while CPT affected the community function more in the high-nutrient system. All treatments show convergence of function, in both light and dark, towards the end of the experiment, whereas the structure remained separated due to the nutrient regime.KEY WORDS: Combined stressors · Sediment · Eutrophication · Copper pyrithione · Nutrient cycling · Microphytobenthos · Bacteria · Meiofauna Resale or republication not permitted without written consent of the publisherAquat Microb Ecol 48: [277][278][279][280][281][282][283][284][285][286][287][288][289][290][291][292][293][294] 2007 rect effects occur when the stressors are combined compared to when acting alone (Skei et al. 2000, Laursen et al. 2002, Millward et al. 2004. Interactions between stressors in a system might cause non-additive effects, giving a totally different response than what would have been the case assuming simple additive effects (Folt et al. 1999).Cloern (2001) has reviewed and described the conceptual models of coastal eutrophication, which include 3 phases. The first 2 phases are fairly simple, and include only the signal of nutrient enrichment and the responses to enrichment. These 2 are relatively well investigated. In the third phase, other stressorsincluding toxicants -are added in combination with nutrient enrichment. This third phase is at present not well studied, and we hope that the present study can contribute information suitable to represent the third phase in a conceptual model.In the present experiment we studied the combined effects of eutrophication and the a...

show abstract

Comparing aquatic risk assessment methods for the photosynthesis-inhibiting herbicides metribuzin and metamitron

Cited by 48 publications

References 24 publications

Combined nutrienttoxicant effects on a shallow-water marine sediment system: sensitivity and resilience of ecosystem functions

Combined nutrienttoxicant effects on a shallow-water marine sediment system: sensitivity and resilience of ecosystem functions

Aquatic Risks of Pesticides, Ecological Protection Goals, and Common Aims in European Union Legislation

Combined effects of an antifouling biocide and nutrient status on a shallow-water microbenthic community

Contact Info

Product

Resources

About

Comparing aquatic risk assessment methods for the photosynthesis-inhibiting herbicides metribuzin and metamitron

Cited by 48 publications

References 24 publications

Combined nutrienttoxicant effects on a shallow-water marine sediment system: sensitivity and resilience of ecosystem functions

Combined nutrienttoxicant effects on a shallow-water marine sediment system: sensitivity and resilience of ecosystem functions

Aquatic Risks of Pesticides, Ecological Protection Goals, and Common Aims in European Union Legislation

Combined effects of an antifouling biocide and nutrient status on a shallow-water microbenthic community

Contact Info

Product

Resources

About

Combined nutrienttoxicant effects on a shallow-water marine sediment system: sensitivity and resilience of ecosystem functions

Combined nutrienttoxicant effects on a shallow-water marine sediment system: sensitivity and resilience of ecosystem functions