Exposure control measures proposed by different organizations: the curious case of nanomaterial-involved activities.

Objectives. The unique properties of nanomaterials have turned them into an emerging threat for humans and the environment. This study therefore aimed to review exposure control measures proposed for nanomaterial-involved activities. Methods. This study is based on the published guidelines of different organizations on safe handling of nanomaterials. The search for documents was provided using the keywords 'Exposure controls', 'Good practices', 'Working safely', 'Safe practices', 'Handling safely', 'Safety guide' and 'Safety and health', combined with 'Nanomaterials', 'Nanotechnology' and 'Nanoparticles' on different databases and websites. Results. Thirty-one guidelines from 27 organizations were included. Most of the guidelines recommended engineering controls, administrative controls and personal protective equipment (PPE). Changing the physical form of nanomaterials or the process, using prevention through design (PtD) and using green chemistry principals were other suggestions to reduce exposure to nanomaterials. Conclusions. Considering the difficulty of implementation and case specificity of the solutions of the first two priorities of the hierarchy of controls (elimination and substitution), the emphasis of the guidelines on the next three priorities for controlling exposure to nanomaterials is understood. The type and method of using PPE and engineering controls should be resolved by referring to cutting-edge articles.

Improving ultraviolet protection properties of cotton textiles using Zinc oxide (ZnO) nanomaterials: an approach for controlling occupational and environmental exposures.

Ultraviolet (UV) radiation exposure is one of the most important risk factor among workers. it may stimulate health outcomes such as multiple skin injuries and blinding eye diseases. So, UV protection is mainly important for people who expose to it. Modification of cotton textiles by nanomaterials is a new approach to overcome this problem. So, the aim of this study is to review studies conducted on using ZnO nanoparticles for improving ultraviolet protection of cotton textiles. The search strategy was provided by cochrane guideline. 45 studies were regarded as appropriate. The results show that UPF for textiles has improved by coated ZnO. However, UPF was depended on the physicochemical characteristics of ZnO and textiles such as yarn structure, effect of woven fabric construction, fabric porosity, and impurity of textiles and laundering conditions. Also, plasma technology has improved UPF, it is recommended that more studies be done to achieve better results.

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.

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.

Investigating the relationship between occupational exposure to nanomaterials and symptoms of nanotechnology companies' employees.

PURPOSE: The increasing use of nanomaterials in academic and industrial environments has raised concerns about the potential effects of these materials on human and the environment. Researches have shown that occupational exposure to nanomaterials can affect employees' health. Many companies are active in the field of nanotechnology in Iran. Therefore, this study was designed and conducted to investigate the relationship between the symptoms of these companies' employees and exposure to nanomaterials. METHODS: The study was conducted among employees of 52 nanotechnology companies in Tehran. For this study, the employees of these companies were categorized in two groups: "exposed" and "non-exposed" to nanomaterials. Data collection tools included the NanoTool method form and a nonspecific symptom questionnaire designed and validated by a team of 19 experts in various fields. Finally, data were analyzed using SPSS.22 software. RESULTS: The results showed that the frequency of cutaneous (such as roughness, itching and redness), respiratory (such as cough, sneezing, and burning throat) and ocular (such as burning, itching and redness) symptoms were higher among the exposed workers to nanomaterials. Examination of the correlation between these symptoms in the two studied groups showed that symptoms with high frequency have a significant relationship with exposure to nanomaterials. CONCLUSIONS: Given the high prevalence of some symptoms among the employees of the studied companies and their association with exposure to nanomaterials, it seems necessary to take control measures to reduce the exposure of employees to nanomaterials and consequently reduce the Investigated symptoms.

Nanosafety: a knowledge, attitude and practice (KAP) study among Iranian researchers working in nanotechnology laboratories.

Objectives. There is a set of evidence about the adverse effects of engineered nanomaterials (ENMs) on humans and the environment. People working with nanomaterials (NMs) (in nanotechnology laboratories and workplaces) are often exposed to these materials. Following nanosafety principals can reduce exposure to ENMs. This study aimed to investigate the knowledge, attitude and practice (KAP) of Iranian researchers toward nanosafety. Methods. This descriptive cross-sectional study was conducted via a questionnaire designed using the results of a literature review and validated by a panel of experts. After completion of questionnaires by Iranian researchers, data were analyzed using SPSS version 20.0. Results. Investigation into the knowledge of study participants showed that 61.38% of them answered the questions correctly. Although 74.34% of the study participants had a proper attitude to nanosafety, only 27.3% of them considered ENMs to be harmful to humans and the environment. Examination of researchers' performance in laboratories showed that 24.25% of them 'always' have good performance. Conclusions. It seems that increasing awareness by teaching the principles of working safely with NMs can help to create a positive attitude toward the principles of nanosafety. Positive attitude can finally lead to the optimal performance of researchers in laboratories involved with NMs.

8-Hydroxy-2'-deoxyguanosine (8-OHdG) as a biomarker of oxidative DNA damage induced by occupational exposure to nanomaterials: a systematic review.

In nuclear and mitochondrial DNA, 8-hydroxy-2'-deoxyguanosine (8-OHdG) is one of the predominant forms of reactive oxygen species (ROSs) lesions, which commonly used as a biomarker for oxidative stress. Studies showed that the different nanomaterials can induce toxicity by ROSs in human body. So, this study is going to review the studies about oxidative DNA damage caused by occupational exposure to nanomaterials, using 8-OHdG biomarker.Systematic review was managed based on Cochrane systematic review guideline. Literature search was conducted in scientific databases with the main terms of "biomarkers," "biological markers," combined with "occupational exposure" and "nanomaterials." All papers in the field of occupational exposure to nanomaterials until 2020 December were included. To evaluate the quality and bias of studies, GRADE method (Grading of Recommendations, Assessment, Development, and Evaluation) was used.Two hundred twenty-six studies were primarily achieved. By considering the inclusion criteria, overall 8 articles were selected. The majority of the studies were classified as the moderate quality studies (six studies). Also, the study-level bias was critical. This review shows that there is a significant relationship between job title and amount of produced nanomaterials and the existence of 8-OHdG. Also, the levels of 8-OHdG can be measured in urine, blood, and inhalation samples by instrumental procedures.Oxidative damages are an important threat for workers exposed to nanomaterial. Blood and EBC 8-OHdG level can be introduced as a biomarker for metal nanomaterials, but urinary 8-OHdG needs to be taken with caution. So, it is recommended that evaluation not be solely based on one biomarker.

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

Purpose. Nanotechnology can be considered one of the greatest developments over the past few decades. Despite many applications of nanomaterials in various fields, there are concerns about their effects on humans and the environment. Therefore, this study was conducted to assess the risk level of activities involving nanomaterials in nanotechnology companies in Tehran, Iran. Materials and methods. After identifying the main activities of 18 nanotechnology companies, these activities were assessed using the NanoTool method, which is a method for assessing risks of activities involving nanomaterials. Data were analyzed using SPSS version 22. Results. The results showed that in six activities (33.30%) the risk level was 4 (RL4), in eight activities (44.40%) the risk level was 3 (RL3) and four activities (22.30%) had risk level 2 (RL2). Also, it was found that 78.88% of the controls used by these companies were not enough to reduce the risks of nanomaterials and need to be upgraded. Conclusions. The high level of risk in the activities involving nanomaterials shows that there are serious problems regarding the safety of nanomaterials in the nanotechnology companies in Tehran, Iran.