Comprehensive estimate of the theoretical maximum daily intake of pesticide residues for chronic dietary risk assessment in Argentina

A chronic dietary risk assessment for pesticide residues was conducted for four age groups of the Argentinian population following the procedure recommended by the WHO. The National Theoretical Maximum Daily Intake (NTMDI) for 308 pesticides was calculated for the first time, using the Maximum Residue Limits (MRLs) from several Argentinean regulations and food consumption data from a comprehensive National Nutrition and Health Survey. The risk was estimated by comparing the TMDI with the Acceptable Daily Intakes (ADI) identified by various sources. Furthermore, for each of the compounds with a TMDI >65% of the ADI, a probabilistic analysis was conducted to quantify the probability of exceeding the ADI. In this study 27, 22, 10, and 6 active ingredients (a.i.) were estimated to exceed the 100% of the ADI for the different population groups: 6–23 month-old children, 2–5 year-old children, pregnant women, and 10–49 year-old women, respectively. Some of these ADI-exceeding compounds (carbofuran, diazinon, dichlorvos, dimethoate, oxydemeton-methyl and methyl bromide) were found in all four of these groups. Milk, apples, potatoes, and tomatoes were the foods that contributed most to the intake of these pesticides. The study is of primary importance for the improvement of risk assessment, regulations, and monitoring activities.     

Assessing the nature of psychological contracts: a validation of six dimensions

The purpose of this study is to develop a feature‐oriented assessment of psychological contracts, an underdeveloped approach to psychological contracts. Relying on theoretical frameworks in psychological contract research, industrial relations studies, and a cross‐national study on psychological contracts, we identify six dimensions that capture the nature of psychological contracts: tangibility, scope, stability, time frame, exchange symmetry, and contract level. We validate this expanded conceptualization of psychological contracts by developing a nomological network and testing it in a large, representative sample of 1106 employees. The results indicate the significance of formal contract characteristics and HR practices as two antecedents shaping the nature of psychological contracts. In addition, the hypothesized relationships between the three dimensions of time frame, exchange symmetry, and contract level with affective commitment are confirmed as well as the relationships between tangibility, scope and flexibility with personal control. The results further indicate the importance of assessing both employer and employee obligations given the differential effect of the contract makers. Copyright © 2004 John Wiley & Sons, Ltd.     

Pesticide usage in California and the United States

In recent years, pesticide usage in the United States has increased markedly. As measured in 1980 for the U.S.A., there were: (1) more than 45 000 individually products registered; (2) more than 1500 active ingredients involved; and (3) about 2.5 billion pounds of active ingredients used annually. Pesticide usage in agriculture has probably peaked and will probably level off and may even decrease in the 1980's because of public health concerns, environmental concerns, lower dose levels of newer pesticides, and the introduction and use of integrated pest management programs and bio-control programs.     

National short-term dietary exposure assessment of a selected group of pesticides in Argentina

ABSTRACT

An evaluation of acute dietary exposure to pesticide residues, applying deterministic and stochastic methods, was performed for a selected group of pesticides in two representative age groups from Argentina. Thus, 28 active ingredients (a.i.) and 75 food items were evaluated for the group of 2–5-year-old children, while 9 a.i. and 59 food items were considered for the 10–49-year-old women group. A deterministic assessment was conducting following the Food and Agriculture Organization (FAO) and World Health Organization (WHO) procedure but using the national maximum residue limits (MRLs) as pesticide residue concentration data, while in the stochastic approach, a theoretical distribution modeled with the available information was used. Food consumption data were obtained from the 2004–2005 comprehensive national nutrition and health survey. The risk was estimated by comparing the short-term dietary exposure with the acute reference dose (ARfD) values for each pesticide-food combination evaluated. In the deterministic assessment, 173 (39.1%) and 40 (31.3%) combinations exceeded the ARfD thresholds for the 2–5-year-old children and 10–49-year-old women groups, respectively. This conservative study generated relevant information as a first stage of acute dietary risk assessment in Argentina.     

Intercultural interaction: A burden on international managers?

This study discusses the applicability of culture shock and cultural distance with respect to intercultural interaction, one of the cross-cultural adjustment dimensions. It examines the relationship of intercultural interaction with length of time in the host country and location of the foreign assignment. This study used a sample of 162 international managers from five multinational companies. The results suggest that the culture shock hypothesis does not hold for intercultural interaction. Rather, intercultural interaction continued to increase over time. The cultural distance hypothesis is also questioned. European managers completing a foreign assignment in Europe showed less intercultural interaction than European managers in North America and Asia. The desirability of intercultural interaction is discussed in the context of the strategic balance between global integration and local responsiveness and the need for dual citizen and mediating persons.     

Using a fisheries ecosystem model with a water quality model to explore trophic and habitat impacts on a fisheries stock: A case study of the blue crab population in the Chesapeake Bay

Recent calls for the development of ecosystem-based fisheries management compel the development of resource management tools and linkages between existing fisheries management tools and other resource tools to enable assessment and management of multiple impacts on fisheries resources. In this paper, we describe the use of the Chesapeake Bay Fisheries Ecosystem Model (CBFEM), developed using the Ecopath with Ecosim (EwE) software, and the Chesapeake Bay Water Quality Model (WQM) to demonstrate how linkages between available modeling tools can be used to inform ecosystem-based natural resource management. The CBFEM was developed to provide strategic ecosystem information in support of fisheries management. The WQM was developed to assess impacts on water quality. The CBFEM was indirectly coupled with the WQM to assess the effects of water quality and submerged aquatic vegetation (SAV) on blue crabs. The output from two WQM scenarios (1985-1994), a baseline scenario representing actual nutrient inputs and another with reduced inputs based on a tributary management strategy, was incorporated into the CBFEM. The results suggested that blue crab biomass could be enhanced under management strategies (reduced nutrient input) when the effective search rate of blue crab young-of-the-year's (YOY's) predators or the vulnerability of blue crab YOY to its predators was adjusted by SAV. Such model linkages are important for incorporating physical and biological components of ecosystems in order to explore ecosystem-based fisheries management options.