Environmental Risks Caused by Pesticides at Forest Nurseries in Finland

ABSTRACT

Previously, various persistent pesticides were used extensively in the production of seedlings at Finnish forest nurseries. The extent and magnitude of the risks arising from the consequent environmental contamination are largely unknown. Therefore, we selected two representative nurseries for which we conducted tiered health risk assessments (HRA) using risk-based benchmarks and two calculation tools (SSL and Risc-Human software). Ecological risk assessments (ERA) involved comparisons of environmental concentrations with ecotoxicological benchmarks. Site investigations revealed that the concentration of several pesticides exceeded the Finnish soil quality guidelines in some places. The compost pile for organic residues and the pond receiving runoffs contained traces of pesticides and the maximum concentration of atrazine and terbuthylazine in groundwater exceeded the corresponding guideline for household water. Hexachlorobenzene proved to pose the highest health risks, the maximum hazard quotient being around 10 (carcinogenity-based) in the residential land use scenario. Owing to the conservative assumptions, health risks are expected to remain insignificant, however. Risks to the local terrestrial ecosystem would also remain low, while only further studies will reveal the actual risks to the adjoining aquatic ecosystem. Both calculation tools showed shortcomings that generate uncertainty in the HRA, whereas the ERA was hampered particularly by the lack of benchmarks.

Key Words:

• forest nursery
• contamination
• risk assessment
• risk management
• pesticides
• Finland

ACKNOWLEDGMENTS

This study was financed by the Finnish Ministry of the Environment. The preparation of the article was financially supported by Kone Foundation, the University of Oulu together with the NorNet network, and Renlund Foundation.

Notes

Such as, Pesticide Action Network's (PAN) Pesticides Database (http://www.panna.org/); EU Pesticides database and committee reports (http://ec.europa.eu/sanco_pesticides/public/index.cfm); Pesticide Properties Database (PPDB, http://sitem.herts.ac.uk/aeru/footprint/en/index.htm); Pesticide Information Profiles available in the EXTension TOXicology NETwork (EXTOXNET, http://extoxnet.orst.edu/); TOXNET databases (http://toxnet.nlm.nih.gov/); the Finnish Data Bank of Environmental Properties of Chemicals (EnviChem); data provided by the USEPA (http://www.epa.gov/pesticides/index.htm); the Finnish pesticide registration and related data.

Pica refers to a medical disorder characterized by an appetite for, for example, substances largely non-nutritive such as soil.