Lawler Sharon P
Department of Entomology and Nematology, University of California, Davis One Shields Avenue, Davis, CA 95616, USA.
Ecotoxicol Environ Saf. 2017 May;139:335-343. doi: 10.1016/j.ecoenv.2016.12.038. Epub 2017 Feb 7.
Some pesticides are applied directly to aquatic systems to reduce numbers of mosquito larvae (larvicides) and thereby reduce transmission of pathogens that mosquitoes vector to humans and wildlife. Sustained, environmentally-safe control of larval mosquitoes is particularly needed for highly productive waters (e.g., catchment basins, water treatment facilities, septic systems), but also for other habitats to maintain control and reduce inspection costs. Common biorational pesticides include the insect juvenile hormone mimic methoprene and pesticides derived from the bacteria Bacillus thuringiensis israelensis, Lysinibacillus sphaericus and Saccharopolyspora spinosa (spinosad). Health agencies, the public and environmental groups have especially debated the use of methoprene because some studies have shown toxic effects on non-target organisms. However, many studies have demonstrated its apparent environmental safety. This review critically evaluates studies pertinent to the environmental safety of using methoprene to control mosquito larvae, and provides concise assessments of the bacterial larvicides that provide sustained control of mosquitoes. The review first outlines the ecological and health effects of mosquitoes, and distinguishes between laboratory toxicity and environmental effects. The article then interprets non-target toxicity findings in light of measured environmental concentrations of methoprene (as used in mosquito control) and field studies of its non-target effects. The final section evaluates information on newer formulations of bacterially-derived pesticides for sustained mosquito control. Results show that realized environmental concentrations of methoprene were usually 2-5µg/kg (range 2-45µg/kg) and that its motility is limited. These levels were not toxic to the vast majority of vertebrates and invertebrates tested in laboratories, except for a few species of zooplankton, larval stages of some other crustaceans, and small Diptera. Studies in natural habitats have not documented population reductions except in small Diptera. Bacterial larvicides showed good results for sustained control with similarly limited environmental effects, except for spinosad, which had broader effects on insects in mesocosms and temporary pools. These findings should be useful to a variety of stakeholders in informing decisions on larvicide use to protect public and environmental health in a 'One Health' framework.
一些杀虫剂被直接应用于水生系统，以减少蚊虫幼虫数量（杀幼虫剂），从而减少蚊子向人类和野生动物传播病原体的情况。对于高产水域（如集水区、水处理设施、化粪池系统），尤其需要持续、环境安全地控制幼虫蚊子，但对于其他栖息地也是如此，以维持控制并降低检查成本。常见的生物合理杀虫剂包括昆虫保幼激素类似物烯虫酯以及源自苏云金芽孢杆菌以色列亚种、球形赖氨酸芽孢杆菌和多杀菌素链霉菌（多杀菌素）的杀虫剂。卫生机构、公众和环境组织尤其对烯虫酯的使用展开了辩论，因为一些研究表明它对非目标生物有毒性作用。然而，许多研究已证明其明显的环境安全性。本综述批判性地评估了与使用烯虫酯控制蚊虫幼虫的环境安全性相关的研究，并对能持续控制蚊子的细菌杀幼虫剂进行了简要评估。该综述首先概述了蚊子的生态和健康影响，并区分了实验室毒性和环境影响。然后，文章根据烯虫酯的实测环境浓度（用于蚊虫控制）及其非目标影响的实地研究来解读非目标毒性研究结果。最后一部分评估了关于用于持续控制蚊子的新型细菌源杀虫剂配方的信息。结果表明，烯虫酯的实际环境浓度通常为2 - 5微克/千克（范围为2 - 45微克/千克），且其移动性有限。除了少数几种浮游动物、其他一些甲壳类动物的幼虫阶段以及小型双翅目昆虫外，这些浓度对实验室测试的绝大多数脊椎动物和无脊椎动物无毒。除了多杀菌素在中型生态系统和临时水塘中对昆虫有更广泛影响外，自然栖息地的研究并未记录到除小型双翅目昆虫外的种群数量减少情况（使用细菌杀幼虫剂）。这些发现对于各种利益相关者在“同一健康”框架下就使用杀幼虫剂保护公众和环境健康做出决策时应是有用的。
