Influence of dioxin-related compounds on physical function in Yusho incident victims

Jun-Ichi Fukushi; Hidetoshi Tsushima; Yoshihiro Matsumoto; Chikage Mitoma; Masutaka Furue; Hisaaki Miyahara; Yasuharu Nakashima

doi:10.1016/j.heliyon.2019.e02702

Influence of dioxin-related compounds on physical function in Yusho incident victims

Heliyon. 2019 Oct 23;5(10):e02702. doi: 10.1016/j.heliyon.2019.e02702. eCollection 2019 Oct.

Authors

Jun-Ichi Fukushi^{1

2}, Hidetoshi Tsushima^{1

2}, Yoshihiro Matsumoto², Chikage Mitoma³, Masutaka Furue³, Hisaaki Miyahara¹, Yasuharu Nakashima²

Affiliations

¹ Department of Rheumatology, Clinical Research Institute, National Hospital Organization Kyushu Medical Center, Jigyohama1-8-1, Chuoh-ku, Fukuoka 810-8583, Japan.
² Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Kyushu University, Maidashi3-1-1, Higashi-ku, Fukuoka 812-8582, Japan.
³ Department of Dermatology, Graduate School of Medical Sciences, Kyushu University, Maidashi3-1-1, Higashi-ku, Fukuoka 812-8582, Japan.

Abstract

Purpose: Few studies have examined the influence of dioxin-related compounds on human physical function, and existing results are inconsistent. In 1968, accidental human exposure to rice oil contaminated with dioxin-related compounds resulted in the development of Yusho oil disease in Japan. We aimed to determine whether the degree of exposure to dioxin-related compounds was associated with physical function in Yusho patients.

Methods: In 2016, 65 men (average age: 65.7 years) and 77 women (average age: 64.7 years) participated in a nationwide health examination in Fukuoka prefecture. Functional reach, gait speed, hand grip strength, and toe grip strength were evaluated as part of physical function. The serum levels of polychlorinated dibenzo-p-dioxin, polychlorinated dibenzofurans, and non-ortho polychlorinated biphenyls were measured using high-resolution gas chromatography and high-resolution mass spectrometry. We examined the association between physical function tests and serum toxic equivalency (TEQ) values.

Results: A 10-fold increase in serum TEQ levels was negatively associated with functional reach (adjusted b = -4.07, p = 0.017) and hand grip strength (adjusted b = -2.20, p = 0.0245) in men. No association was observed between serum TEQ level and physical function in women.

Conclusion: Our findings suggest that dioxin-related compounds have a negative influence on physical function in men. However, these findings should be interpreted carefully. Future studies examining additional data on musculoskeletal disorders are warranted.

Keywords: Dioxin; Environmental health; Environmental science; Environmental toxicology; Epidemiology; Functional reach; Hand grip strength; Musculoskeletal system; Physical activity; Physical function; Toxicology; Yusho.