Assessing the risk of main activities of nanotechnology companies by the NanoTool method

An integrated approach to occupational health risk assessment of manufacturing nanomaterials using Pythagorean Fuzzy AHP and Fuzzy Inference System

Nanomaterials (NMs) have the potential to be hazardous owing to their unique physico-chemical properties. Therefore, the need for Health Risk Assessment (HRA) of NMs is expanding. In this study, a novel HRA was developed by the Pythagorean Fuzzy Health Risk Assessment (PFHRA) approach. Risk is considered to be the outcome of parameters including Occurrence Likelihood (OL), Potential Exposure (PE) and Toxic Effects (TE). In our proposed method, priority weights of sub-factors in Pythagorean Fuzzy-Analytical Hierarchical Process (PF-AHP) were determined by pairwise comparison based on expert judgment. After determining parameter scores, both RM and risk class (i.e., negligible, minor, major and critical) were reported as Fuzzy Inference System (FIS) output. Ultimately, a risk management strategy is presented for NMs manufacturing workplaces. This proposed method provides experts with more flexibility to express their opinions. The PFHRA approach was applied for two scenarios. The production scenario for SiNPs can create minor (5%) and major (95%) occupational health risks; the production scenario for ZnONPs can create minor (100%) concerns. However, the production SiNPs and ZnONPs utilizing the CB Nanotool technique had a major and minor risk class, respectively. The results of the present study confirmed the reliability and applicability of this approach.

An analysis on control banding-based methods used for occupational risk assessment of nanomaterials

Despite all benefits of nanomaterials, their unique characteristics made them an emerging hazard in workplaces, which need to be assessed for their potential risks. So, the aim of this study was to review all the studies conducted on the risk assessment of activities involving nanomaterials with CB-based methods.This study is based on a literature review on databases including Web of science, Scopus, PubMed, and SID. After reviewing and screening studies according to PRISMA, the collected data were meta-analyzed by Comprehensive Meta-Analysis Software. Also, Newcastle-Ottawa checklist was used for quality assessment of the studies. To determine similarity of methods, Cohen's Kappa was used. Sensitivity analysis was used to determine the role of each factor in the risk assessment by using the Crystal Ball tool.There are eight validated methods for risk assessment. Also, some authors used a self-deigned tool based on CB approach. The results of meta-analysis showed that the odds ratio for the risk of activities involved with nanomaterials was 0.654 (high risk). Results of simulation for Nanotool showed that the mean risk level of activities involved with nanomaterials, with a certainty of 95.07%, is moderate (RL3). Moreover, sensitivity analysis showed that the risk was depended on "Hazard band" in all methods except ISO method.The obtained results can be useful in improving existing methods and suggesting new methods. Also, there is a need to design and propose specific methods for risk assessment of incidental and natural nanomaterials.

Laboratory activities involving nanomaterials: risk assessment and investigating researchers symptoms

The increasing use of nanomaterials is a threat to human health and environment that has led to the expansion of risk assessment methods. Thus, the aim of this study was to assess the occupational risks of activities involving nanomaterials in nanomedicine research laboratories by Control Banding (CB) NanoTool and Guidance methods. Further, the symptoms of researchers working in these laboratories were investigated. This cross-sectional study was managed in nanomedicine research laboratories. Risk assessment was performed by the CB NanoTool and Guidance methods. Moreover, a questionnaire was used to assess the prevalence of non-specific symptoms. Finally, data were analyzed using the IBM SPSS software. Descriptive statistics were used for data analysis. Many activities are located on the risk level RL2 and category A based on the CB NanoTool and Guidance methods, respectively. Further, the highest severity of exposure to nanomaterials belonged to the preparation of suspension and emulsion and manufacture of metal nanopolymers, but the highest probability of exposure was in the manufacturing of carbon nanocomposites. In addition, there was a significant relationship between the level of risk in the two methods (P = 0.003). Although, cutaneous symptoms were the most common symptoms among laboratory researchers, chi-square test did not confirm any significant relationship between symptoms and risk levels (p-value >0.05) in these two methods. Since the NanoTool method uses more diverse parameters for risk assessment and is more acceptable, choosing control measures based on its results seems more reasonable. Moreover, Guidance can be used as a method for initial assessments and determine the need for further assessments.

Oxidative stress induced by occupational exposure to nanomaterials: a systematic review

The rapid growth of nanotechnology has increased the occupational exposure to nanomaterials. On the other hand, a growing body of evidence considers exposure to these materials to be hazardous. Therefore, it is necessary to examine the effects of occupational exposure to these materials by different methods. Biological monitoring, especially the investigation of oxidative stress induced by exposure to nanomaterials, can provide useful information for researchers. This study systematically reviews studies that have investigated oxidative stress caused by occupational exposure to nanomaterials. The search was conducted on the PubMed, Scopus and Web of Science databases. Of the 266 studies we obtained in our initial search, eventually 11 were included in our study. There is currently no specific biomarker for investigating oxidative stress induced by exposure to nanomaterials. Therefore, the reviewed studies have used different biomarkers in different biological fluids for this purpose. Also, the methods of assessing occupational exposure to nanomaterials in the investigated studies were very diverse. Given the approach of the investigated studies to biomarkers and exposure assessment methods, finding a specific biomarker for investigating exposure to nanomaterials seems unattainable. But reaching a group of biomarkers, to assess exposure to nanomaterials seems more applicable and achievable.