299 resultados para Chemical workers


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Fifty-nine persons with industrial handling of low levels of acrylonitrile (AN) were studied. As part of a medical surveillance programme an extended haemoglobin adduct monitoring [N-(cyanoethyl)valine, CEV; N- (methyl)valine, MV; N-(hydroxyethyl)valine, HEV] was performed. Moreover, the genetic states of the polymorphic glutathione transferases GSTM1 and GSTT1 were assayed by polymerase chain reaction (PCR). Repetitive analyses of CEV and MV in subsequent years resulted in comparable values (means, 59.8 and 70.3 μg CEV/1 blood; 6.7 and 6.7 μg MV/1 blood). Hence, the industrial AN exposures were well below current official standards. Monitoring the haemoglobin adduct CEV appears as a suitable means of biomonitoring and medical surveillance under such exposure conditions. There was also no apparent correlation between the CEV and HEV or CEV and MV adduct levels. The MV and HEV values observed represented background levels, which apparently are not related to any occupational chemical exposure. There was no consistent effect of the genetic GSTM1 or GSTT1 state on CEV adduct levels induced by acrylonitrile exposure. Therefore, neither GSTM1 nor GSTT1 appears as a major AN metabolizing isoenzyme in humans. The low and physiological background levels of MV were also not influenced by the genetic GSTM1 state, but the MV adduct levels tended to be higher in GSTT1- individuals compared to GSTT1 + persons. With respect to the background levels of HEV adducts observed, there was no major influence of the GSTM1 state, but GST- individuals displayed adduct levels that were about 1/3 higher than those of GSTT1+ individuals. The coincidence with known differences in rates of background sister chromatid exchange between GSTT1- and GSTT1 + persons suggests that the lower ethylene oxide (EO) detoxification rate in GSTT1- persons, indicated by elevated blood protein hydroxyethyl adduct levels, leads to an increased genotoxic effect of the physiological EO background.

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The high priority of monitoring workers exposed to nitrobenzene is a consequence of clear findings of experimental carcinogenicity of nitrobenzene and the associated evaluations by the International Agency for Research on Cancer. Eighty male employees of a nitrobenzene reduction plant, with potential skin contact with nitrobenzene and aniline, participated in a current medical surveillance programme. Blood samples were routinely taken and analysed for aniline, 4-aminodiphenyl (4-ADP) and benzidine adducts of haemoglobin (Hb) and human serum albumin (HSA). Also, levels of methaemoglobin (Met-Hb) and of carbon monoxide haemoglobin (CO-Hb) were monitored. Effects of smoking were straightforward. Using the rank sum test of Wilcoxon, we found that very clear-cut and statistically significant smoking effects (about 3-fold increases) were apparent on CO-Hb (P = 0.00085) and on the Hb adduct of 4-ADP (P = 0.0006). The mean aniline-Hb adduct level in smokers was 1.5 times higher than in non-smokers; the significance (P = 0.05375) was close to the 5% level. The strongest correlation was evident between the Hb and HSA adducts of aniline (rs = 0.846). Less pronounced correlations (but with P values < 0.02) appeared between aniline-Hb and 4-ADP-Hb adducts (rs = 0.388), between 4-ADP and 4-ADP-HSA adducts (rs = 0.373), and between 4-ADP-Hb and aniline-HSA adducts (rs = 0.275). In view of the proposal for additional use of the aniline-HSA adduct for biological monitoring, particularly in cases of acute overexposures or poisonings, the strong correlation of the Hb and HSA conjugates is noteworthy; the ratio aniline-HSA:aniline-Hb was 1:42 for the entire cohort.

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The specific mechanisms by which selective pressures affect individuals are often difficult to resolve. In tephritid fruit flies, males respond strongly and positively to certain plant derived chemicals. Sexual selection by female choice has been hypothesized as the mechanism driving this behaviour in certain species, as females preferentially mate with males that have fed on these chemicals. This hypothesis is, to date, based on studies of only very few species and its generality is largely untested. We tested the hypothesis on different spatial scales (small cage and seminatural field-cage) using the monophagous fruit fly, Bactrocera cacuminata. This species is known to respond to methyl eugenol (ME), a chemical found in many plant species and one upon which previous studies have focused. Contrary to expectation, no obvious female choice was apparent in selecting ME-fed males over unfed males as measured by the number of matings achieved over time, copulation duration, or time of copulation initiation. However, the number of matings achieved by ME-fed males was significantly greater than unfed males 16 and 32 days after exposure to ME in small cages (but not in a field-cage). This delayed advantage suggests that ME may not influence the pheromone system of B. cacuminata but may have other consequences, acting on some other fitness consequence (e.g., enhancement of physiology or survival) of male exposure to these chemicals. We discuss the ecological and evolutionary implications of our findings to explore alternate hypotheses to explain the patterns of response of dacine fruit flies to specific plant-derived chemicals.

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Reconfiguration of corporate structures and the retailer-supplier interface in the retail industry have restructured product markets and supply chains, as well as supermarket employment, over the past decade or so (Baret, Lehndorff & Sparks 2000; du Gay 1996). Various studies have examined the consequent changes in labour usage practices within supermarkets or superstores (Baret et al. 2000; Marchington 1995; Penn & Wirth 1993; Sparks 1992; Dawson, Findlay & Sparks 1987, 1986). Commonly, this literature explores the interplay between shifts in the structure of the labour market, broader societal trends and retailers’ employment strategies. One study found that domestic and gender dimensions, accompanied by industrial relations regimes, exert considerable influence on patterns of labour usage (Baret et al. 2000). However, while the types of labour usage and the drivers of changes to labour usage patterns have attracted significant academic attention, research has largely overlooked the ways in which the nature of supermarket work has evolved as a result of changing technology, which effectively bolsters managerial prerogative, and which has affected the skill levels of workers in the industry (Marchington 1995).

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The purpose of this paper is to explore the changing nature of employee voice through trade union representation in the retail industry. The retail industry is a major employer in the UK and is one of the few private sector service industries with union representation (Griffin et al 2003). The requisite union: the Distributive and Allied Workers (USDAW) union is one of the biggest unions in the country. However, the characteristics of the industry provide unique challenges for employee voice and representation including: high labour turnover; high use of casual, female and student labour; and, variable levels of union recognition (Reynolds et al 2005). Irrespective of these challenges, any extension of representation and organisation by unions in the retail sector is inherently valuable, socially and politically, given that retail workers are often categorised as vulnerable, due to the fact that they are among the lowest paid in the economy, sourced from disadvantages labour markets and increasingly subject to atypical employment arrangements (Broadbridge 2002; Henley 2006; Lynch 2005; Roan 2003).

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Aim: To investigate workplace cultures in the acquisition of computer usage skills by mature age workers. Methods: Data were gathered through focus groups conducted at job network centres in the Greater Brisbane metropolitan region. Participants who took part were a mixture of workers and job-seekers. Results: The results suggest that mature age workers can be exposed to inappropriate computer training practices and age-insensitive attitudes towards those with low base computer skills. Conclusions: There is a need for managers to be observant of ageist attitudes in the work place and to develop age-sensitive strategies to help mature age workers learn computer usage skills. Mature age workers also need to develop skills in ways which are practical and meaningful to their work.

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This paper is a comparative exploratory study of the changing nature of employee voice through trade union representation in the retail industry in the UK and Australia. In both countries, the retail industry is a major employer and is one of the few private sector service industries with significant union membership (Griffin et al 2003). The relevant unions, the Distributive and Allied Workers Union (USDAW) and the Shop, Distributive and Allied Union (SDA), are the fourth largest and largest unions in the UK and Australia respectively. However, despite this seeming numerical strength in membership, the characteristics of the industry provide unique challenges for employee voice and representation. The significance of the study is that any extension of representation and organisation by unions in the retail sector is valuable socially and politically, given that retail workers are often categorised a s vulnerable, due to their low pay, the predominance of disadvantaged labour market groups such a s women and young people, workers’ atypical employment arrangements and, in the case of the UK, variable levels of union recognition which inhibit representation (Broadbridge 2002; Henley 2006; Lynch 2005; Roan & Diamond 2003; Reynolds et al 2005). In addition, specifically comparative projects have value in that they allow some variables relating to the ‘industry’ to be held constant, thus reducing the range of potential explanations of differences in union strategy. They also have value in that the research partners may be more likely to notice and problematise taken-for-granted aspects of practices in another country, thus bringing to the fore key features and potentially leading to theoretical innovation. Finally, such projects may assist in transnational diffusion of union strategy.

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This paper reports on an empirically based study of the Queensland (Australia) health and fitness industry over 15 years (1993 -2008). This study traces the development of the new occupation of fitness instructor in a service industry which has evolved si nce the 1980s and is embedded in values of consumption and individualism. It is the new world of work. The data from the 1993 study was historically significant, capturing the conditions o f employment in an unregulated setting prior to the introduction of the first industrial a ward in that industry in 1994. Fitness workers bargained directly with employers over all a spects of the employment relationship without the constraints of industrial regulation or the presence of trade unions. The substantive outcomes of the employment relationship were a direct reflection of m anagerial prerogative and worker orientation and preference, and did not reflect the rewards and outcomes traditionally found in Australian workplaces. While the focus of the 1993 research was on exploring the employment relationship in a deregulated environment, an unusual phenomenon was identified: fitness workers happily trading-off what would be considere d standard working conditions for the opportunity to work (‘take the stage’). Since then, several streams of literature have evolved providing a new context for understanding this phenomenon in the fitness industry, including: the sociology of the body (Shilling 1993; Turner 1996); emotional (Hochschild 1984) and aesthetic labour (Warhurst et al 2000); the so cial relations of production and space (Lefebvre 1991; Moss 1995); body history (Helps 2007); the sociology of consumption (Saunders 1988; Baudrillard 1998; Ritzer 2004); and work identity (Du Gay 1996; Strangleman 2004). The 2008 survey instrument replicated the 1993 study but was additionally informed b y the new literature. Surveys were sent to 310 commercial fitness centres and 4,800 fitness workers across Queensland. Worker orientation appears unchanged, and industry working conditions still seem atypical despite regulation si nce 1994. We argue that for many fitness workers the goal is to gain access to the fitness centre economy. For this they are willing to trade-off standard conditions of employment, and exchange traditional employm ent rewards for m ore intrinsic psycho-social rewards gained the through e xp o sure of their physical capital (Bourdieu 1984) o r bo dily prowess to the adoration o f their gazing clients. Building on the tradition of emotional labour and aesthetic labour, this study introduces the concept of ocularcentric labour: a state in which labour’s quest for the psychosocial rewards gained from their own body image shapes the employment relationship. With ocularcentric labour the p sycho-social rewards have greater value for the worker than ‘hard’, core conditions of employment, and are a significant factor in bargaining and outcomes, often substituting fo r direct earnings. The wo rkforce profile (young, female, casual) and their expectations (psycho-social rewards of ado ration and celebrity) challenge traditional trade unions in terms of what they can deliver, given the fitness workers’ willingness to trade-off minimum conditions, hard-won by unions.