A review of occupational health and safety risk assessment approaches based on multi-criteria decision-making methods and their fuzzy versions

Occupational health and safety (OHS) is a multidisciplinary activity working under the tasks of protection of workers and worksites. Risk assessment, as a compulsory process in implementation of OHS, stands out as evaluating the risks arising from the hazards, taking into account the required control measures, and deciding whether or not the risks can be reduced to an acceptable level. The diversity in risk assessment approaches is such that there are many methods for any industry. Multicriteria decision-making (MCDM)-based approaches contribute to risk assessment knowledge with their ability on solving real-world problems with multiple, conflicting, and incommensurate criteria. This article conducts a critical state-of-the-art review of OHS risk assessment studies using MCDM-based approaches. Additionally, it includes fuzzy versions of MCDM approaches applied to OHS risk assessment. A total of 80 papers are classified in eight different application areas. The papers are reviewed by the points of publication trend, published journal, risk parameters/factors, and tools used. This critical review provides an insight for researchers and practitioners on MCDM-based OHS risk assessment approaches in terms of showing current state and potential areas for attempts to be focused in the future.     

The US national antimicrobial resistance monitoring system.

The use of antimicrobial agents in food animals can select for resistant bacterial pathogens that may be transmitted to humans via the commercial meat supply. In the USA, the FDA's Center for Veterinary Medicine regulatory duties require a determination that antimicrobial drugs are safe and effective for use in food animals. In addition, a qualitative assessment of risks to human health from antimicrobial resistance requires development. This risk assessment process is supported by data generated by the FDA's National Antimicrobial Resistance Monitoring System (NARMS) for enteric bacteria. NARMS data on antimicrobial susceptibility among Salmonella, Campylobacter, Escherichia coli and Enterococcus is collected. Research activities defining the genetic bases of resistance helps to understand the potential public health risks posed by the spread of antimicrobial resistance from food animal antimicrobial use. These activities help insure that antimicrobials are used judiciously to promote human and animal health.     

Significance of biocide usage and antimicrobial resistance in domiciliary environments

Recent events have raised awareness of the need for effective hygiene in the home. Not least is the requirement to reduce antibiotic resistance by reducing the need for antibiotic prescribing. Current evidence suggests that improved hygiene in the domestic setting could have a significant impact. Recently, it has been suggested that widespread biocide usage, particularly in consumer products, may be a contributory factor in antibiotic resistance. In developing home hygiene policies, however, it is important that biocide use as an integral part of good hygiene practice is not discouraged in situations where there is real benefit. Although laboratory data indicate possible links, it is necessary to assess whether and to what extent biocide exposure could contribute to antibiotic resistance in clinical practice. The extent to which reduced susceptibility to biocides resulting from biocide exposure could compromise their 'in-use' effectiveness must also be considered. Equally, it is important that changes in susceptibility induced by biocide exposure are assessed relative to those induced by antibiotic exposure or the phenotypic changes induced by 'normal' environmental 'stresses'. It is proposed that to be effective, home hygiene policy should be based on the concept of risk assessment and risk prevention. Using this approach, critical risk situations are identified and appropriate hygiene procedures applied to reduce risks. This may involve either soap and water cleaning, or cleaning combined with a disinfection process. A 'targeted' hygiene approach not only provides the most effective means of preventing infectious disease, it also offers a means of addressing concerns about 'too much hygiene' and 'too many antibacterials' amongst a public who have lost confidence regarding appropriate hygiene for their home environment.     

Current and future needs for developmental toxicity testing

A review is presented of the use of developmental toxicity testing in the United States and international regulatory assessment of human health risks associated with exposures to pharmaceuticals (human and veterinary), chemicals (agricultural, industrial, and environmental), food additives, cosmetics, and consumer products. Developmental toxicology data are used for prioritization and screening of pharmaceuticals and chemicals, for evaluating and labeling of pharmaceuticals, and for characterizing hazards and risk of exposures to industrial and environmental chemicals. The in vivo study designs utilized in hazard characterization and dose-response assessment for developmental outcomes have not changed substantially over the past 30 years and have served the process well. Now there are opportunities to incorporate new technologies and approaches to testing into the existing assessment paradigm, or to apply innovative approaches to various aspects of risk assessment. Developmental toxicology testing can be enhanced by the refinement or replacement of traditional in vivo protocols, including through the use of in vitro assays, studies conducted in alternative nonmammalian species, the application of new technologies, and the use of in silico models. Potential benefits to the current regulatory process include the ability to screen large numbers of chemicals quickly, with the commitment of fewer resources than traditional toxicology studies, and to refine the risk assessment process through an enhanced understanding of the mechanisms of developmental toxicity and their relevance to potential human risk. As the testing paradigm evolves, the ability to use developmental toxicology data to meet diverse critical regulatory needs must be retained.     

Probabilistic Analysis of Human Health Risks Associated with Background Concentrations of Inorganic Arsenic: Use of a Margin of Exposure Approach

Substantial evidence exists from epidemiological and mechanistic studies supporting a sublinear or threshold dose–response relationship for the carcinogenicity of ingested arsenic; nonetheless, current regulatory agency evaluations have quantified arsenic risks using default, generic risk assessment procedures that assume a linear, no-threshold dose–response relationship. The resulting slope factors predict risks from U.S. background arsenic exposures that exceed certain regulatory levels of concern, an outcome that presents challenges for risk communication and risk management decisions. To better reflect the available scientific evidence, this article presents the results of a Margin of Exposure (MOE) analysis to characterize risks associated with typical and high-end background exposures of the U.S. population to arsenic from food, water, and soil. MOE values were calculated by comparing a no-observable-adverse-effect-level (NOAEL) derived from the epidemiological literature with exposure estimates generated using a probabilistic (Monte Carlo) model. The plausibility and conservative nature of the exposure and risk estimates evaluated in this analysis are supported by sensitivity and uncertainty analyses and by comparing predicted urinary arsenic concentrations with empirical data. Using the more scientifically supported MOE approach, the analysis presented in this article indicates that typical and high-end background exposures to inorganic arsenic in U.S. populations do not present elevated risks of carcinogenicity.     

Adaptation of amoebae to cooling tower biocides

Adaptation of amoebae to four cooling tower Biocides, which included a thiocarbamate compound, tributyltin neodecanoate mixed with quaternary ammonium compounds (TBT/QAC), another QAC alone, and an isothiazolin derivative, was studied. Previously we found that amoebae isolated from waters of cooling towers were more resistant to cooling tower biocides than amoebae from other habitats. Acanthamoeba hatchetti and Cochliopodium bilimbosum, obtained from American Type Culture Collection and used in the previous studies, were tested to determine whether they could adapt to cooling tower Biocides. A. hatchetti was preexposed to subinhibitory concentrations of the four Biocides for 72h, after which they were tested for their resistance to the same and other biocides. C. bilimbosum was exposed to only two biocides, as exposure to the other two was lethal after 72 h. Preexposure to the subinhibitory concentrations of the Biocides increased the resistance of the amoebae, as indicated by a significant increase in the minimum inhibitory concentration (up to 30-fold). In addition, cross-resistance was also observed, i.e., exposure to one biocide caused resistance to other biocides. These results show that amoebae can adapt to biocides in a short time. The phenomenon of cross-resistance indicates that regularly alternating biocides, as is done to control microbial growth in cooling towers, may not be effective in keeping amoeba populations in check. On the contrary, exposure to one biocide may boost the amoebae's resistance to a second biocide before the second biocide is used in the cooling tower. Since amoebae may harbor Legionella, or alone cause human diseases, these results may be important in designing effective strategies for controlling pathogens in cooling towers. Correspondence to: S.G. Berk.     

Possible implications of biocide accumulation in the environment on the prevalence of bacterial antibiotic resistance

The lethality of biocides depends upon their interaction with a number of distinct biochemical targets. This often reflects reactive chemistry for any given agent, such as thiol oxidation. Susceptibility may vary markedly between different target organisms, and changes within the more sensitive targets can alter the inhibitory effect. The multiplicity of potential targets, however, usually dictates against the development of overt resistance to concentrations used for hygienic applications. Similarly, although changes in cellular permeability toward such agents, mediated either by envelope modification or the induction of efflux-pumps may reduce susceptibility, they rarely influence the outcome of treatments at use-concentration. It has recently been proposed that chronic exposure of the environment to biocides used in a variety of commercial products might expose some microbial communities to subeffective concentrations causing emergence of resistant clones. Such resistance might relate to mutational changes in the most susceptible target or to regulatory mutants that cause the constitutive expression of certain efflux pumps. Although selection of organisms with such modifications is unlikely to influence the effectiveness of the biocides, changes in their susceptibility to third-party antibiotics can be postulated. This is particularly the case where a cellular target is shared between a biocide and an antibiotic, or where induction of efflux is sufficient to confer antibiotic resistance in the clinic. Although such linkage has been demonstrated in the laboratory in pure culture, it has not been documented in environments commonly exposed to biocides. In nature, the effects of chronic stressing with biocides are complicated by competition between microbial community members that may result in clonal expansion of naturally insusceptible clones. Received 11 March 2002/ Accepted in revised form 16 August 2002     

A blueprint for the problem formulation phase of EPA-type ecological risk assessments for 316(b) determinations

The difference between management objectives focused on sustainability of fish populations and the indigenous aquatic community, and a management objective focused on minimizing entrainment and impingement losses accounts for much of the ongoing controversy surrounding paragraph 316(b). We describe the EPA's ecological risk assessment framework and recommend that this framework be used to more effectively address differences in management objectives and structure paragraph 316(b) determinations. We provide a blueprint for the problem formulation phase of EPA-type ecological risk assessments for cooling-water intake structures (CWIS) at existing power plant facilities. Our management objectives, assessment endpoints, conceptual model, and generic analysis plan apply to all existing facilities. However, adapting the problem formulation process for a specific facility requires consideration of the permitting agency's guidelines and level of regulatory concern, as well as site-specific ecological and technical differences. The facility-specific problem formulation phase is designed around the hierarchy of biological levels of organization in the generic conceptual model and the sequence of cause-effect events and risk hypotheses represented by this model. Problem formulation is designed to be flexible in that it can be tailored for facilities where paragraph 316(b) regulatory concern is low or high. For some facilities, we anticipate that the assessment can be completed based on consideration of susceptibility alone. At the other extreme, a high level of regulatory concern combined with the availability of extensive information and consideration of costly CWIS mitigation options may result in the ecological risk assessment relying on analyses at all levels. Decisions on whether to extend the ecological risk assessment to additional levels should be based on whether regulatory or generator concerns merit additional analyses and whether available information is adequate to support such analyses. In making these decisions, the functional dependence between levels of analysis must be considered in making the transition to the analysis phase and risk estimation component of the ecological risk assessment. Regardless of how the generic analysis plan is modified to develop a facility-specific analysis plan, the resulting plan should be viewed as a tool for comparing representative species and alternative CWIS options by focusing on relative changes (i.e., proportional or percent changes) in various measures. The analysis plan is specifically designed to encourage consideration of multiple lines of evidence and to characterize uncertainties in each line of evidence. Multiple lines of evidence from different levels of analysis, obtained using both prospective and retrospective techniques, provide a broader perspective on the magnitude of potential effects and associated uncertainties and risks. The implications of the EPA's recent (April 2002) proposed regulations for existing facilities on the applicability of this blueprint are briefly considered.     

Applying a weed risk assessment approach to GM crops

Current approaches to environmental risk assessment of genetically modified (GM) plants are modelled on chemical risk assessment methods, which have a strong focus on toxicity. There are additional types of harms posed by plants that have been extensively studied by weed scientists and incorporated into weed risk assessment methods. Weed risk assessment uses robust, validated methods that are widely applied to regulatory decision-making about potentially problematic plants. They are designed to encompass a broad variety of plant forms and traits in different environments, and can provide reliable conclusions even with limited data. The knowledge and experience that underpin weed risk assessment can be harnessed for environmental risk assessment of GM plants. A case study illustrates the application of the Australian post-border weed risk assessment approach to a representative GM plant. This approach is a valuable tool to identify potential risks from GM plants.     

The effect of fifteen biocides on formaldehyde-resistant strains ofPseudomonas aeruginosa

Summary Evaluation of formaldehyde and fifteen biocides in formaldehyde sensitive (S) and resistant (R) strains ofPseudomonas aeruginosa revealed a pattern of response that allowed a comparison of the mode of action of these biocides. The response of these strains to the various biocides, as well as the induction of transient resistance or cross-resistance in the (S) strain, allowed a grouping of biocides based on this pattern of response. Group 1 biocides acted in a manner indistinguishable from formaldehyde for both the (S) and (R) strains. Group 2 biocides were not effective against either the (S) or (R) strains at concentrations calculated to release equimolar concentrations of formaldehyde. However, treatment of the (S) strain with formaldehyde or Group 2 biocides resulted in the development of cross-resistance. Group 3 biocides were equally effective against the (S) and (R) strain, but the (S) strain survivors of treatment with Group 3 biocides were resistant to formaldehyde. Group 4 biocides (controls) had no presumed connection to formaldehyde mode of action. These four groupings, based on pattern of response, also resulted in groupings of biocides based on chemical structure.     

Assessment and management of human health risk from biocides

The assessment and management of human health risk from biocides is an iterative and multidisciplinary scientific process that seeks to define the inherent hazards of the material and integrate this information with the details of potential human exposure. This paper attempts to outline the critical elements and relationships in this process while presenting the risk assessment process for Kathon microbicides (blend of isothiazolones, 3:1 ratio of 5-chloro-2-methyl-4-isothiazolin-3-one and 2-methyl-4-isothiazolin-3-one: MCI/MC) as an illustrative example.     

Current status of pyrethroid resistance in anophelines

Similarities between DDT and pyrethroid insecticides have led to widespread concern that cross-resistance between them might limit the usefulness of the latter. Both types of insecticide have similarities in chemical structure, both have a negative temperature coefficient (ie. they are more active at lower temperatures), both act as neurotoxins on sodium channels, and both produce the twin effects of knockdown and kill. As discussed by Tom Miller (see pages S8-S12) there is firm evidence for Pyrethroid resistance in some species of medical and veterinary importance - especially in the horn fly, Haemotobia irritans. But in the case of anopheline mosquitoes, the evidence for pyrethroid resistance is much less strong. As Colin Malcolm explains here, a critical analysis of available data indicates that true physiological resistance of anophelines to pyrethroids is much less widespread than previous commentaries suggest. Moreover, the risk of cross-resistance between pyrethroids and DDT may have been over-emphasized, since different resistance mechanisms appear to be involved.     

Adaptation of Campylobacter jejuni to biocides used in the food industry affects biofilm structure,adhesion strength,and cross-resistance to clinical antimicrobial compounds

The emergence of biocide-adapted Campylobacter jejuni strains that developed into biofilms and their potential to develop clinical resistance to antimicrobial compounds was studied. C. jejuni was grown in sub-lethal concentrations of five biocides used in the food industry. C. jejuni exhibited adaptation to these biocides with increased minimum inhibitory concentrations. The 3-D structures of the biofilms produced by the biocide-adapted cells were investigated by atomic force microscopy (AFM). The results revealed marked variability in biofilm architecture, including ice-crystal-like structures. Adaptation to the biocides enhanced biofilm formation, with significant increases in biovolume, surface coverage, roughness, and the surface adhesion force of the biofilms. Adaptation to commercial biocides induced resistance to kanamycin and streptomycin. This study suggests that the inappropriate use of biocides may lead to cells being exposed to them at sub-lethal concentrations, which can result in adaptation of the pathogens to the biocides and a subsequent risk to public health.     

Need to determine the relative developmental risks of Fusarium mycotoxin dexoynivalenol (DON) and Benomyl (BEN) in wheat

The wheat supply is known to have levels of deoxynivalenol (DON) from fungal infections. The fungal infections can be suppressed with benomyl (BEN). Under certain exposure laboratory conditions DON and BEN are developmental toxins. Since use of BEN may result in concurrent dietary exposure to both compounds, evaluation of the relative developmental risks is needed. The dietary NOAELs for pup decreased body weight for DON and BEN are 0.375 mg/kg/day in mice and 5 mg/kg/day in rat, respectively. Human exposure to DON can be estimated from surveys of wheat grain and finished products which gave a mean DON concentration of 0.86 ppm. The tolerance level for BEN in grain is 0.2 ppm. Presence of DON and BEN in wheat at these concentrations would not impact wheat consumption. A modified margin of exposure (modMOE) was developed using “a”; kg (food) /kg (body weight) as the constant for wheat consumption. The modMOE for DON is 28/a and that for BEN is 1667/a. Comparative relative risks can be expressed as the ratio of BEN risks to DON risks (60). Treatment with BEN at the most efficacious time decreased DON levels to 34% of controls, and decreased the comparative risk ratio from 60 to 18. The potential for fungicides to decrease mycotoxin health risks is important in the safety assessment for foodstuffs. This approach improves on current practices for food safety assessment by including the expected reductions in risks from naturally occurring mycotoxins in the regulatory analysis.     

Lifestyle and fertility: the influence of stress and quality of life on female fertility

There is growing evidence that lifestyle choices account for the overall quality of health and life (QoL) reflecting many potential lifestyle risks widely associated with alterations of the reproductive function up to the infertility. This review aims to summarize in a critical fashion the current knowledge about the potential effects of stress and QoL on female reproductive function. A specific literature search up to August 2017 was performed in IBSS, SocINDEX, Institute for Scientific Information, PubMed, Web of Science and Google Scholar. Current review highlights a close relationship in women between stress, QoL and reproductive function, that this association is more likely reported in infertile rather than fertile women, and that a vicious circle makes them to have supported each other. However, a precise cause-effect relationship is still difficult to demonstrate due to conflicting results and the lack of objective measures/instruments of evaluation.     

<Emphasis Type="Italic">Pseudomonas aeruginosa</Emphasis> PAO1 adapted to 2-phenoxyethanol shows cross-resistance to dissimilar biocides and increased susceptibility to antibiotics

The growth adaptability to increasing concentration of the biocide 2-phenoxyethanol (PE) was determined in Pseudomonas aeruginosa PAO1 (P.a.) as part of efforts to understand and control the biocide tolerance and its effect on cross-resistance to other biocides and resistance to antibiotics. After repeated subculturing in media containing increasing sub-minimum-inhibitory PE concentration, P.a. exhibited an adaptive resistance indicated by two-fold increase in MIC at the 10th passage. The resistance was stable and remained after passaging the strain in further 7 successive passages in PE-free growth media. The strain showed cross-resistance towards dissimilar biocides and displayed increased susceptibility to antibiotics, which was not influenced by the presence of the efflux inhibitor ‘carbonyl cyanide m-chlorophenyl hydrazone’. Outer membranes of adapted strain showed altered protein profile when examined by SDS-PAGE.     

环境耐药组及其健康风险的宏基因组学研究策略和方法

抗生素耐药性在环境中的发展和传播对人体健康造成潜在风险。随着高通量测序技术和生物信息学方法的不断发展,宏基因组学技术被广泛应用于不同环境样本的抗生素耐药组研究。本文介绍了两种针对环境耐药组筛查的宏基因组学分析方法,总结了当前主流的生物信息学软件和数据库,并阐述了环境耐药组的风险评估框架和基于宏基因组学技术的相关实践,以期为环境耐药组的监测、风险评估和管控提供可行的路线图。     

Low level of cross-resistance between triclosan and antibiotics in Escherichia coli K-12 and E. coli O55 compared to E. coli O157

Misuse of biocides has encouraged the emergence of resistance and cross-resistance in certain strains. This study investigated resistance of triclosan-adapted Escherichia coli K-12 and E. coli O55 to antimicrobial agents and compared these to E. coli O157:H7. Cross-resistance in E. coli K-12 and E. coli O55 was observed however to a lesser extent than in E. coli O157:H7. Triclosan-adapted E. coli K-12 demonstrated cross-resistance to chloramphenicol, whereas triclosan-adapted E. coli O55 exhibited resistance to trimethoprim. In comparison, E. coli O157:H7 was resistant to chloramphenicol, tetracycline, amoxicillin, amoxicillin/clavulanic acid, trimethoprim, benzalkonium chloride and chlorohexidine suggesting strain specific rather than general resistance mechanisms.     

EC/US workshop report: assessment of genetic risks associated with exposure to ethylene oxide, acrylamide, 1,3-butadiene and cyclophosphamide

The EC/US Workshop on Risk Assessment: ‘Human Genetic Risks from Exposure to Chemicals, Focusing on the Feasibility of a Parallelogram Approach’ had as its main objective the identification of the methodology, data requirements and mechanistic research to understand the human health impact of germ cell mutagens. Specifically, it represented an evaluation of current knowledge and the identification of future research needs for a more precise assessment of human genetic risks from exposure to mutagenic chemicals. Four chemicals were selected for review at the Workshop and in this Special Issue: ethylene oxide, 1,3-butadiene, acrylamide, and cyclophosphamide. The first three are important industrial chemicals with substantial use worldwide and, therefore, considerable potential for human exposure. The fourth, cyclophosphamide, is a commonly used cancer chemotherapeutic agent. This Special Issue contains the major scientific reports from the workshop. These include four Introductory Papers (on the parallelogram concept, alternative genetic risk assessment approaches, regulatory data needs, and the research background for risk assessment of ethylene oxide), four Working Group Reports on the specific compounds mentioned above and, finally, three Crosscutting Papers pertinent to the issue of germ-line mutagenesis and genetic risk estimation.