Effects of droplet density and concentration on the efficacy of bacillus thuringiensis and carbaryl against gypsy moth larvae (Lymantria dispar L.)

Abstract

The feeding behavior of gypsy moth larvae exposed to two pesticide deposits (Bt and carbaryl) on oak leaf disks was monitored to determine the relationships between its efficacy and application parameters (droplet density and pesticide concentration). A range of pesticide concentrations and droplet densities (from 9 to 149 droplets/cm²) was used to simulate high and low application rates produced by different methods of application in the field.

The LD₅₀ and the LC₅₀, appeared to be affected by the spatial distribution of the deposit on the leaf surface. Both Bt and carbaryl showed a decreasing LD₅₀ at increasing time after spray. The LD₅₀ of Bt decreased from 14.1 BIU/liter to 3.1 BIU/Iiter between 48 and 144 hours after spray. The results show that feeding inhibition by Bt is more closely related to concentration than to droplet density and dose per unit area with the highest feeding inhibition occurring at 10 BIU/liter at 9 droplets/cm². With carbaryl, an increase in both concentration and droplet density was necessary to cause a decrease in leaf area eaten by larvae.     

Revision of deposition and weathering parameters for the ingestion dose module (ECOSYS) of the ARGOS and RODOS decision support systems

The ECOSYS model is the ingestion dose model integrated in the ARGOS and RODOS decision support systems for nuclear emergency management. The parameters used in this model have however not been updated in recent years, where the level of knowledge on various environmental processes has increased considerably. A Nordic work group has carried out a series of evaluations of the general validity of current ECOSYS default parameters. This paper specifically discusses the parameter revisions required with respect to the modelling of deposition and natural weathering of contaminants on agricultural crops, to enable the trustworthy prognostic modelling that is essential to ensure justification and optimisation of countermeasure strategies. New modelling approaches are outlined, since it was found that current ECOSYS approaches for deposition and natural weathering could lead to large prognostic errors.     

北京环境辐射水平现状与分布

在北京市按网格布点调研了环境辐射水平。北京原野γ辐射及宇宙射线室外剂量率按网点加权均值分别为５６．２及３２．３ｎＧｙ·ｈ＾－１,全市土壤中＾２３８Ｕ,＾２３２Ｔｈ,＾２２６Ｒａ,＾４０Ｋ及＾１３７Ｃｓ含量按面积加权均值分别为１９．４,３４．１,２１．４,６２２及８．３Ｂｑ·ｋｇ＾－１,各类水体水中Ｕ,Ｔｈ及＾２６Ｒａ,＾４０Ｋ浓度范围分别是０．１２－８．９４,０．０２－０．６６μｇ·Ｌ＾－１及６．     

Elemental and radioactivity analysis of rocks and soils of some selected sites in southwestern Nigeria

The elemental and radioactivity analyses of rock and soil samples from some selected sites in southwestern Nigeria have been done. Measurements of the elemental compositions and activity concentrations of ²³⁸U, ²³²Th, and ⁴⁰K were carried out using nuclear activation analysis technique and gamma spectrometry with high purity germanium detector, respectively. The results obtained provide reference data, allowing observation of possible future changes due to future radiological contamination. The activity concentrations of the natural radionuclides measured in the rocks were higher than those of the soils. The mean concentration of the major and minor elements in the rock and soil samples followed the order Al > Ca > Na > K > Mg > Fe > Ti and Mn > Ba > V > As > Cr > Ni > Zn > Cu, respectively. The radiological hazard and pollution risks associated with the natural radionuclides and heavy metals in the samples were assessed. The results obtained for the annual effective dose equivalent (AEDE), internal hazard, external hazard, and representative gamma indices were lower than their respective maximum permissible limit of 1 mSv y^?1 for AEDE and 1 for internal hazard, external hazard, and representative gamma indices as recommended by the International Commission on Radiological Protection (ICRP). The results of the geo-accumulation index, enrichment factor, and the pollution load index indicate that the soils of the study area are uncontaminated with the heavy metals measured except Ado-Ekiti, Ikere, and Igbara-Odo soils which are moderately contaminated with Arsenic (As).     

A qualitative investigation of factors affecting school district administrators’ decision to adopt a national young worker curriculum

Introduction: Even though the majority of youth in the U.S. work, and workers under the age of 18 are seriously injured on the job at higher rates when compared to adults, most adolescents lack instruction on workplace safety and health. Method: This qualitative study examines the extent to which selected U.S. school districts provide workplace safety and health instruction to students and explores the factors that influence districts’ decision to adopt a free, foundational occupational safety and health (OSH) curriculum. Results: Results from key informant interviews conducted with a purposive sample of 34 school administrators revealed that only a third of the districts have at least 75% of their students receive some instruction on workplace safety and health, while 15% indicated they provide no instruction on this topic. District staff who indicated that they provide OSH instruction stated that it is most often taught through career and technical education (CTE; 65%) and/or health classes (26%). They believed the benefits of providing this instruction include assisting students to get jobs (38%) and helping students learn about safety (32%), while competing demands (44%) and time constraints (41%) were identified as barriers to providing OSH education to students. Conclusions: Given the importance of work to teens and their increased risk of work injury, interested stakeholders—including parents, teachers, employers, and the public health community—should promote the inclusion of workplace safety and health instruction in U.S. secondary schools. Practical Applications: This research fills a gap in current knowledge about the extent to which OSH is currently taught within U.S. secondary schools, enumerates barriers and facilitators to the inclusion of workplace safety and health instruction in schools, presents a free, foundational curriculum in workplace safety and health, and provides directions for future research on the vital role schools can play in preparing the future workforce for safe and healthy employment.     

Safety climate at agricultural cooperatives

Introduction: This study identifies determinants of safety climate at agricultural cooperatives. Methods: An extensive survey was designed to build upon past research done in collaboration with DuPont (Risch et al., 2014). In 2014 and 2015, the survey was administered to 1930 employees at 14 different agricultural cooperatives with 154 locations. Injury incidence data were also collected from each location to better understand the overall health and safety environment in this sector. An ordered probit model is used to identify variables that are associated with better safety climates. Results: Safety system components such as discipline programs, inspection programs, modified duty programs, off-the-job safety training programs, and recognition programs are positively related to individual safety climate for both managerial employees and nonmanagerial employees. Variables representing an employee’s agricultural background, distance between their workplace and childhood home, and formal education are not associated with managerial safety climate. However, agricultural background and childhood home distance are associated with nonmanagerial safety climate. Conclusions: Improving occupational health and safety is a priority for many agricultural cooperatives. Lower safety climate emerges as nonmanagerial employees have more experience with production agriculture and work nearer to their home community. Practical applications: Employees of agricultural cooperatives face a host of health and safety challenges that are likely to persist into the future. The safety system components associated with safety climate indicate that continuous feedback is important for improving occupational health and safety. Occupational health and safety programming should also acknowledge that many employees have experiences that influence their attitudes and behaviors.     

Evaluation and comparison of the Chinese policy context for safety-related psychological health in the workplace: Realities,gaps and challenges

Work-related psychological health problems have become a major challenge for occupational health and safety (OHS) management. Hard and soft policy systems could be employed to guarantee that this issue is taken seriously and solved effectively. However, in China, compared with the European Union (EU) and Australia, few experts have reviewed the policies related to this area. Thus, a comparative analysis was performed to investigate the hard and soft law policies associated with safety-related psychological health in the workplace based on approved criteria. A total of 21 policies (16 hard and 5 soft) were evaluated, and the current realities were discovered. Then, by comparing the actual situation in China with that of countries with well-developed policy systems in this area, extant gaps and future challenges were observed. The results showed that both hard and soft policies addressed the topic, but all of them had rather low scores. The policy system is far from perfect and is still in its infancy in China, and there are great gaps between China and countries with more developed systems related to this topic. Filling these gaps may involve encountering some challenges in the future. Based on the analysis, some specific suggestions are recommended to promote the policy system and improve OHS management from the perspective of psychological health related to work.     

某铁路隧道作业场所职业危害风险控制效果评价

为了解铁路隧道作业场所职业病危害特征,评估其职业病危害风险控制效果,采用现场调查与职业病危害因素检测相结合的方法,对某铁路隧道作业场所职业病危害特征进行调查,采用职业病危害风险指数评估模型进行控制效果评估。结果表明,该铁路隧道作业场所职业危害因素主要包括生产过程中职业病危害、劳动过程中危害和生产环境中危害;主要职业病危害因素为电焊烟尘、矽尘、NO、NO2、CO、CO2、噪声、振动、高湿等;隧道内工务、电务、供电三大线路作业场所的线路维护人员接触的噪声均为轻中度危害,氮氧化物(NO、NO2)为轻度危害,接触的CO为中高度危害,线路维护人员矽尘作业岗位为轻中高度危害,易导致职业病损的发生。提出应重点监控该铁路隧道接触噪声、CO和矽尘的作业岗位,采取科学综合防控措施,改善作业环境质量,强化个人防护。     

Data mining for occupational injuries in the Taiwan construction industry

There is a higher rate of occupational injury in the construction industry than most other industries on average. However, steps can be taken to reduce worker risk through effective injury prevention strategies. In this article, association rule mining is employed in identifying the characteristics of occupational injuries in the construction industry. Accident reports during the period 1999–2004 are extracted from case reports of the Northern Region Inspection Office of the Council of Labor Affairs of Taiwan. In addition to general factors, several factors related to weather conditions are included in this article. The results show that there are some patterns of occupational injuries in the construction industry. The effect of rain on the occurrence of fatalities is of great significance. Proposed inspection plans should be in accordance with the type of construction and environmental evaluation. The findings identified in this article provide a direction for more effective inspection strategies and injury prevention programs.     

Differences in the lethality of occupational accidents in OECD countries

International comparisons of the frequency of occupational accidents are rare because figures reported by each country are influenced by factors other than differences in the occurrence of actual accidents. In this study, we performed an international comparison of occupational accidents which distinguishes between fatal cases and all reported accidents, in order to control for the effects of other factors in accident reporting. Annual data on the numbers of fatal and non-fatal occupational accidents in member countries of the Organisation for Economic Co-operation and Development (OECD) between 1993 and 1998 were obtained from the Labour Statistics Database, which is operated by the International Labour Organization (ILO). The average incidence of all accidents across OECD countries ranged from 17 to 4608 per 100,000 persons in the labor force, whereas the incidence of fatal accidents across OECD countries ranged from 1 to 12 per 100,000 persons in the labor force. Lethality rates per 10,000 total accident cases ranged from 9 (Germany) to 3252 (Turkey). When comparing countries using the same statistical definition of accidents, three or more absence days, the difference in lethality of reported accidents within the same industrial sector is reduced to a sixfold difference (49 for the United Kingdom versus 333 for Ireland). Furthermore, the difference in lethality decreased to about twofold (18 for Spain versus 35 for Czech Republic) in the group using definitions with a criteria of one absent day. The results suggest that reported differences in lethality can reflect artificial administrative factors rather than the harmful factors that cause actual occupational accidents. To make more valid comparison of occupational accident between countries, harmonization of accident statistics is required.