A laboratory study on risk assessment of microcystin-RR in cropland

• Published in: Journal of environmental management Vol. 86; no. 3; pp. 566 - 574
• Main Authors: Bibo, Liu, Yan, Gong, Bangding, Xiao, Jiantong, Liu, Yongding, Liu
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.02.2008; Elsevier; Academic Press Ltd
• Subjects: Adsorption; agricultural soils; Agriculture; Animal, plant and microbial ecology; Applied ecology; Biodegradation; Biodegradation of pollutants; Biodegradation, Environmental; Biological and medical sciences; Biotechnology; Brassica napus; Brassica rapa subsp. chinensis; cabbage; Carcinogens - analysis; Carcinogens - chemistry; Chromatography; Chromatography, High Pressure Liquid - methods; Conservation, protection and management of environment and wildlife; Crop plants; Cropland soils; Crops; Crops, Agricultural - drug effects; Crops, Agricultural - growth & development; Crops, Agricultural - metabolism; duration; Environment and pollution; Environmental behavior; Evaluation; Flora; Fundamental and applied biological sciences. Psychology; General aspects; high performance liquid chromatography; humic acids; Industrial applications and implications. Economical aspects; Irrigation; irrigation water; Kinetics; laboratories; Microcystin-RR; microcystins; Microcystins - adverse effects; Microcystins - analysis; Microcystins - chemistry; organic fertilizers; Peptides; Persistence time; plant growth; plant growth substances; provenance; Risk; Risk Assessment; Soil Microbiology; Soil Pollutants - analysis; Soil pollution; Soils; solutions; sprouting; Toxicity; water pollution; China; Biodegradation; Adsorption; Environmental behavior; Cropland soils; Microcystin-RR; Crop plants; Persistence time; Laboratory study; Risk analysis; Environmental management; Persistence; Soils; Plant; Behavior
• ISSN: 0301-4797; 1095-8630
• DOI: 10.1016/j.jenvman.2006.12.040

The persistence time and risk of microcystin-RR (MC-RR) in cropland via irrigation were investigated under laboratory conditions. In order to evaluate the efficiency of the potential adsorption and biodegradation of MC-RR in cropland and the persistence time of MC-RR for crop irrigation, high performance liquid chromatography (HPLC) was used to quantify the amount of MC-RR in solutions. Our study indicated that MC-RR could be adsorbed and biodegraded in cropland soils. MC-RR at 6.5 mg/L could be completely degraded within 6 days with a lag phase of 1–2 days. In the presence of humic acid, the same amount of MC-RR could be degraded within 4 days without a lag phase. Accordingly, the persistence time of MC-RR in cropland soils should be about 6 days. This result also suggested the beneficial effects of the organic fertilizer utilization for the biodegradation of MC-RR in cropland soils. Our studies also demonstrated that MC-RR at low concentration (<10 μg/L) could accelerate the growth of plants, while high concentration of MC-RR (>100 μg/L) significantly inhibited the growth of plants. High sensitivity of the sprouting stage plants to MC-RR treatments as well as the strong inhibitory effects resulting from prolonged irrigation further indicated that this MC-RR growth-inhibition may vary with the duration of irrigation and life stage of the plants.