Jacques Malchaire

Bio: Jacques Malchaire is an academic researcher from Université catholique de Louvain. The author has contributed to research in topics: Trunk & Population. The author has an hindex of 27, co-authored 92 publications receiving 2417 citations. Previous affiliations of Jacques Malchaire include Catholic University of Leuven & The Catholic University of America.

Review of the factors associated with musculoskeletal problems in epidemiological studies.

Abstract: Objectives: To review systematically all epidemiological studies of the past 15 years concerning the factors associated with musculoskeletal disorders (MSDs) or complaints of the neck and upper limbs. Methods: Fifty-seven cross-sectional and seven longitudinal studies were reviewed. A list was made of all personal, occupational, extra-occupational and psycho-organisational factors taken into consideration in each study, and of those that were found in association with MSDs. MSDs of the neck-shoulder region (NSs) and hand-wrist (HWs) were considered separately. About 70 different factors are listed. Results: This inventory identifies the factors or categories of factors that were generally taken into consideration. It makes it possible also to evaluate the strength of the association with a given factor, in considering the number of studies finding an association, and those that did not consider this factor. Based on this review, some factors taken into consideration (such as weight or hobbies) could be excluded in further studies, and replaced by more specific psycho-organisational factors.

Development and validation of the predicted heat strain model

Abstract: Eight laboratories participated in a concerted research project on the assessment of hot working conditions. The objectives were, among others, to co-ordinate the work of the main European research teams in the field of thermal factors and to improve the methods available to assess the risks of heat disorders at the workplace, and in particular the "Required Sweat Rate" model as presented in International Standard ISO 7933 Standard (1989). The scientific bases of this standard were thoroughly reviewed and a revised model, called "Predicted Heat Strain" (PHS), was developed. This model was then used to predict the minute by minute sweat rates and rectal temperatures during 909 laboratory and field experiments collected from the partners. The Pearson correlation coefficients between observed and predicted values were equal to 0.76 and 0.66 for laboratory experiments and 0.74 and 0.59 for field experiments, respectively, for the sweat rates and the rectal temperatures. The change in sweat rate with time was predicted more accurately by the PHS model than by the required sweat rate model. This suggests that the PHS model would provide an improved basis upon which to determine allowable exposure times from the predicted heat strain in terms of dehydration and increased core temperature.

Surveillance of workers exposed to mercury vapour: Validation of a previously proposed biological threshold limit value for mercury concentration in urine

Abstract: A cross-sectional epidemiological study was carried out among subjects exposed to mercury (Hg) vapour, ie, a group of 131 male workers (mean age: 30.9 yr; average duration of exposure, 4.8 yr) and a group of 54 female workers (mean age, 29.9 yr; average duration of exposure 7 yr). The results were compared with those obtained in well-matched control groups comprising 114 and 48 male and female workers, respectively. The intensity of current Hg vapour exposure was rather moderate as reflected by the levels of mercury in urine (HgU) (mean and 95th percentile: males 52 and 147 micrograms/g creatinine; females 37 and 63 micrograms/g creatinine) and of mercury in blood (mean and 95th percentile: males 1.4 and 3.7 micrograms/dl; females 0.9 and 1.4 microgram/dl). Several symptoms mainly related to the central nervous system (memory disturbances, depressive feelings, fatigue, irritability) were more prevalent in the Hg-exposed subjects. They were, however, not related to exposure parameters. In both male and female Hg-exposed workers no significant disturbances were found in short-term memory (audioverbal), simple reaction time (visual), critical flicker fusion, and colour discrimination ability. Only slight renal tubular effects were detected in Hg-exposed males and females, ie, an increased urinary beta-galactosidase activity and an increased urinary excretion of retinol-binding protein. The prevalence of these preclinical renal effects was more related to the current exposure intensity (HgU) than to the duration of exposure and was detected mainly when HgU exceeds 50 micrograms/g creatinine. Changes in hand tremor spectrum recorded with an accelerometer were found in the Hg-exposed males only. The prevalence of abnormal values for some hand tremor parameters (total velocity and total displacement in the 2-50-Hz band) was mainly increased in male workers exposed for more than 10 yr. Unlike the renal tubular effects, the preclinical signs of tremor were more related to the integrated exposure than to the current exposure. Since the female workers, who have been exposed to Hg vapour levels usually insufficient to increase their HgU levels above 50 micrograms/g creatinine, did not exhibit any change in hand tremor pattern, the results of the present study tend to validate our previously proposed biological threshold limit value of a HgU of 50 micrograms/g creatinine for workers chronically exposed to mercury vapour.

WBGT Index Revisited After 60 Years of Use

Abstract: The Wet Bulb Globe Temperature (WBGT) seems to be still used world widely for the evaluation of heat stress conditions and it is recommended by ISO and American Conference of Governmental Industrial Hygienists as a screening method. Unfortunately, many occupational health practitioners and users appear to be unaware of its limitations. As the ISO 7243 Standard, based on WBGT, is presently under revision, it is an appropriate time to review the validity and applicability of this empirical approach to evaluate heat stress. This article underlines the main issues about the WBGT index from a rational perspective.

Out of the Crisis

Abstract: According to W. Edwards Deming, American companies require nothing less than a transformation of management style and of governmental relations with industry. In Out of the Crisis, originally published in 1982, Deming offers a theory of management based on his famous 14 Points for Management. Management's failure to plan for the future, he claims, brings about loss of market, which brings about loss of jobs. Management must be judged not only by the quarterly dividend, but by innovative plans to stay in business, protect investment, ensure future dividends, and provide more jobs through improved product and service. In simple, direct language, he explains the principles of management transformation and how to apply them.

Toxic effects of metals

Abstract: Essentiality Toxicity Carcinogenicity Lead(Pb) Exposure Toxicokinetics Toxicity Neurologic, Neurobehavioral, and Developmental Effects in Children Mechanisms of Effects on the Developing Nervous System Peripheral Neuropathy Hematologic Effects Renal Toxicity Lead and Gout Effects on Cardiovascular System Immunotoxicity Bone Effects Reproductive Effects Birth Outcomes Carcinogenicity Other Effects Dose Response Treatment Organic Lead Compounds Mercury (Hg) Exposure Disposition and Toxicokinetics Metabolic Transformation Cellular Metabolism Toxicology Biological Indicators Treatment Nickel (Ni) Exposure Toxicokinetics Essentiality Toxicity Nickel Carbonyl Poisoning Dermatitis Indicators of Nickel Toxicity

Risk factors for work-related musculoskeletal disorders: a systematic review of recent longitudinal studies

Abstract: Objective This systematic review was designed and conducted in an effort to evaluate the evidence currently available for the many suggested risk factors for work-related musculoskeletal disorders. Methods To identify pertinent literature we searched four electronic databases (Cinahl, Embase, Medline, and The Cochrane Library). The search strategies combined terms for musculoskeletal disorders, work, and risk factors. Only case–control or cohort studies were included. Results A total of 1,761 non-duplicated articles were identified and screened, and 63 studies were reviewed and integrated in this article. The risk factors identified for the development of work-related musculoskeletal disorders were divided and organized according to the affected body part, type of risk factor (biomechanical, psychosocial, or individual) and level of evidence (strong, reasonable, or insufficient evidence). Conclusions Risk factors with at least reasonable evidence of a causal relationship for the development of work-related musculoskeletal disorders include: heavy physical work, smoking, high body mass index, high psychosocial work demands, and the presence of co-morbidities. The most commonly reported biomechanical risk factors with at least reasonable evidence for causing WMSD include excessive repetition, awkward postures, and heavy lifting. Additional high methodological quality studies are needed to further understand and provide stronger evidence of the causal relationship between risk factors and work-related musculoskeletal disorders. The information provided in this article may be useful to healthcare providers, researchers, and ergonomists interested on risk identification and design of interventions to reduce the rates of work-related musculoskeletal disorders. Am. J. Ind. Med. 2009. 2009 Wiley-Liss, Inc.

Epidemiology of low back pain.

Abstract: Low back pain is a symptom that cannot be validated by an external standard. It is a disorder with many possible etiologies, occurring in many groups of the population, and with many definitions. Low back pain is a common problem, with a prevalence in the United States ranging from 8% to 56%. It is estimated that 28% experience disabling low back pain sometime during their lives, 14% experience episodes lasting at least 2 weeks, 8% of the entire working population will be disabled in any given year, and the lifetime prevalence of low back pain is 65% to 80%. It is believed that most episodes of low back pain will be short-lived and that 80% to 90% of attacks of low back pain resolve in about 6 weeks, irrespective of the administration or type of treatment. However, multiple studies in the late 90s showed recurrent or chronic low back pain, evaluated at 3 months, 6 months, or 12 months, ranging from 35% to 79%. Risk factors of low back pain are multifactorial, with many possible etiologies. Multiple risk factors of low back pain and lower-extremity pain include physical factors, social demographic characteristics, habits, and psychosocial factors. This review will discuss the epidemiology of low back pain, with emphasis on frequency, causes, and consequences of low back pain; the influence of age, gender, morphologic characteristics, and genetics; and the influence of occupational, mechanical, social, habitual, and psychological factors.