The influence of indoor air on personal exposure to volatile organic compounds and its risk estimation

This paper summarizes the results of personal exposure monitoring and estimates the risk from exposure to 18 volatile organic compounds compared with health criteria set by the US Environmental Protection Agency. In study 1, personal exposure levels and outdoor air concentrations were compared, and in study 2, personal exposure levels and the corresponding indoor air concentrations were compared. From these studies, it was concluded that personal exposure to volatile organic compounds depended markedly on indoor air quality and that handling of compounds increased personal exposure markedly. Risk estimations indicated that chloroform in tap water, benzene from cigarette smoke and p -dichlorobenzene from household insecticide needed caution.     

Hybrid Surveys: A Method for the Effective Use of Open-Ended Questions in Quantitative Food Choice Surveys

Surveys are based on predetermined questions (PDQs), used in hypothesis testing. To validate surveys, an open-ended question (OEQs), probing for additional factors, is sometimes added. This approach could become more efficient by combining PDQs with OEQs in hybrid surveys. This study surveyed Japanese consumers on seafood quality (n?=?200). It started with three OEQs, asking participants to list the most important factors when evaluating packed mackerel fillets, before they assessed 26 PDQs on importance of different quality dimensions for the same products. The OEQs were grouped based on the PDQs and the answers were counted. The PDQs were rated on 7-point importance scales. The real-life relevance of PDQs was challenged based on the frequency counts of OEQs. The result revealed that the color, overall freshness, and price issues are the most important factors consumers consider in real life. The use of hybrid surveys led to increased validity of this study.     

The economics of on-farm processing: model development and an empirical analysis

Recent trends in the developments of the Common Agricultural Policy suggest an increasing attention towards rural development issues. On-farm processing may offer an alternative for diversification, income generation and rural development in the event of increasingly deregulated agricultural markets. In this study, the economics of on-farm processing for the case of the Swedish potato industry is examined. An interregional partial equilibrium model is developed. Various stages of the potato marketing chain are explicitly modelled. It is empirically demonstrated that, in some regions, on-farm processing is a part of a socially optimal industry structure. Furthermore, it is shown that on-farm processors are more robust towards import competition than bulk product producers. Hence, the results support the notion that small scale processing may contribute towards satisfying some of the objectives of an effective rural development agenda.     

Risk assessment of the flavonoids,quercetin as an endocrine modifier

Flavonoids are constituents of a wide variety of plants and are consumed in vegetables, fruits and certain medicines. They display a dual character with respect to their pharmacological effects and potential toxicity. Recent studies have demonstrated that the flavonoid, quercetin promotes estradiol-induced tumorigenesis by elevating the level of its oestrogen metabolite. Flavonoids have been also characterized as a type of environmental oestrogen. In the present study, we evaluated whether quercetin is a potential carcinogen by consideration of its oestrogenic characteristics, as described in various reports. A complete database review of flavonoids including quercetin revealed that quercetin is only mutagenic in bacterial testing systems and is a weak carcinogenic in rodents, but there has been little evidence that quercetin is tumour-inducing in humans. National Toxicology Program (1992) showed that the nonobserved adverse effect level (NOAEL) is to be less than 416 mg kg^-1 body weight day^-1 for inducing renal tumours in rats. In a study of male hamsters, it has been found that when co-administrated with estradiol, quercetin had a NOAEL of 300 mg kg^-1 day^-1 corresponding to 0.3% of the diet and contributed to the development of estradiol-induced renal tumours in these animals. By employing a 200-fold safety factor to compensate for interspecies variation, intraspecies variation and pharmacokinetics/pharmacodynamics variation, the acceptable daily intake (ADI) was estimated to be 1.5 mg kg^-1 day^-1. It was concluded that the average daily intake of quercetin exceeds this ADI value, suggesting that the risk of developing cancer from this flavonoid is not negligible given the wide exposure to quercetin in our daily life.     

Cost-effective nitrogen leaching reduction as influenced by linkages between farm-level decisions

This article focuses on how the linkages between various farm‐level decisions affect the choice of measures to reduce nitrogen leaching from crop production. A mathematical programming model is developed. The model considers not only management decisions that affect nitrogen leaching directly, but also other decision variables such as scheduling of field operations and machinery investments. A simplified analysis that ignores the latter management decisions, and the linkages between the various decisions, may result in abatement policies that are not cost‐effective because the policies will have other effects than expected. As an example, the empirical results show that subsidies to catch crops and spring ploughing may contribute to increased nitrogen load, quite contrary to the purpose of these subsidies. Further, it is noted that the characteristics of the production system make it costly to change land use, tillage practices, or fertilizer use drastically. Instead, cost‐effective nitrogen abatement includes a mix of various adjustments of farm‐level production practices. The EU set‐aside payment appears to reduce abatement costs.