Naphthalene: irritative and inflammatory effects on the airways

Abstract

Objective This cross-sectional study determined whether acute sensory irritative or (sub)chronic inflammatory effects of the eyes, nose or respiratory tract are observed in employees who are exposed to naphthalene at the workplace. Methods Thirtynine healthy and non-smoking male employees with either moderate (n = 22) or high (n = 17) exposure to naphthalene were compared to 22 male employees from the same plants with no or only rare exposure to naphthalene. (Sub)clinical endpoint measures included nasal endoscopy, smell sensitivity, self-reported work-related complaints and the intensity of naphthalene odor and irritation. In addition, cellular and soluble mediators in blood, nasal lavage fluid (NALF) and induced sputum (IS) were analysed. All measurements were carried out pre-shift on Monday and post-shift on Thursday. Personal air monitoring revealed naphthalene shift concentrations up to 11.6 mg/m3 with short-term peak concentrations up to 145.8 mg/m3 and 1- and 2-naphthol levels (sum) in post-shift urine up to 10.1 mg/L. Results Acute sensory irritating effects at the eyes and upper airways were reported to occur when directly handling naphthalene (e.g., sieving pure naphthalene). Generally, naphthalene odor was described as intense and unpleasant. Habituation effects or olfactory fatigue were not observed. Endoscopic examination revealed mild inflammatory effects at the nasal mucosa of exposed employees in terms of reddening and swelling and abnormal mucus production. No consistent pattern of cellular and soluble mediators in blood, NALF or IS was observed which would indicate a chronic or acute inflammatory effect of naphthalene in exposed workers. Conclusions The results suggest that exposure to naphthalene induces acute sensory irritative effects in exposed workers. No (sub)chronic inflammatory effects on the nasal epithelium or the respiratory tract could be observed under the study conditions described here.

Health Effects of Naphthalene Exposure: A Systematic Evidence Map and Analysis of Potential Considerations for Dose–Response Evaluation

“…Table 1 summarizes the evidence base for respiratory effects of naphthalene exposure, consisting of studies that reported nasal or pulmonary outcomes. The evidence base for human respiratory effects consisted of a medium confidence study that evaluated inflammatory effects and sensory irritation in workers exposed to naphthalene in the abrasives industry ( Sucker et al. 2021 ) and a medium confidence study that evaluated changes in lung function associated with residential levels of volatile organic compounds (VOCs) ( Cakmak et al.…”

“…Sucker et al. ( 2021 ) used a cross-sectional cross-week design with pre- and post-shift outcome measurements and is suitable for dose–response analysis based on the study design and exposure measurements; however, the applicability for reference value derivation is somewhat limited because the outcome measurements are not generally considered to be apical health effects (self-reported nose and eye irritation; redness and mucus measured via otorhinolaryngological examination; and inflammatory biomarkers in serum, nasal lavage, or sputum). The study by Cakmak et al.…”

“…The evidence base for human respiratory effects consisted of a medium confidence study that evaluated inflammatory effects and sensory irritation in workers exposed to naphthalene in the abrasives industry (Sucker et al 2021) and a medium confidence study that evaluated changes in lung function associated with residential levels of volatile organic compounds (VOCs) (Cakmak et al 2014). Sucker et al (2021) used a crosssectional cross-week design with pre-and post-shift outcome measurements and is suitable for dose-response analysis based on the study design and exposure measurements; however, the applicability for reference value derivation is somewhat limited because the outcome measurements are not generally considered to be apical health effects (self-reported nose and eye irritation; redness and mucus measured via otorhinolaryngological examination; and inflammatory biomarkers in serum, nasal lavage, or sputum). The study by Cakmak et al (2014) used a crosssectional study design that has limited ability to assess temporality between exposure and effect, and therefore this study would be more useful for hazard identification than for the derivation of a reference value.…”

Investigating the Potency of Camphor Combined With Kerosene on the Emergence of Anopheles Gambiae

“…Notwithstanding, other aspects of camphor use have been outlined. A study by Sucker et al 30 has reported that camphor can cause mild acute inflammatory irritation of eyes and nose characterized by redness and swollen eyes as well as severe nasal mucus in industrial workers constantly exposed to inhaling it. Fu et al31 opined that they can cause high mortality in insects with reduce exposure time.…”

1,2-dihydroxynaphthalene as Biomonitoring of Occupational Exposure to Naphthalene

“…In addition, symptoms of headache, malaise, and confusion also appear in some people exposed to naphthalene. When exposure is eliminated, symptoms may gradually disappear (Abdel-Shafy and Mansour, 2016;Gupta, 2016;Sucker et al, 2021).…”