Low frequency of infertility among workers in a borate processing facility

Boron Workers in China

This article describes the lifestyle patterns of boron mining and processing workers ( N = 936) and a comparison group ( N = 251) in northeast China, and explores relationships between boron exposure and reproductive health. An English version of an interview guide addressing areas of work and lifestyle relevant to boron exposure and metabolism was developed by an occupational health research team, translated to Chinese, and translated back, for clarity. Modifications incorporated suggestions from a local community advisory board and boron industry workers; the translation–back translation process was reapplied, and cultural and semantic equivalence was attained. Results from the interviews showed more than 64% of workers and comparison group participants smoked tobacco and more than 92% reported exposure to environmental tobacco smoke. Boron workers and the comparison group varied in their food intake and alcohol consumption, but not in their smoking habits. Thirty-four percent of boron workers reported eating in the contaminated work area. Nearly all boron workers (99%) showered or bathed after work, although approximately 10% redressed in their contaminated clothes. Reproductive health outcomes were explored, including delayed pregnancy, multiple births, spontaneous miscarriages, induced abortions, stillbirths, and an unusual ratio of male to female offspring. Implications for occupational health nurses and recommendations for future research are provided.

Boron exposure assessment using drinking water and urine in the North of Chile

Boron is an essential trace element for plants and humans however it is still an open question what levels of boron are actually safe for humans. This study, conducted between 2006 and 2010, measured exposure levels of boron in drinking water and urine of volunteers in Arica, an area in the North of Chile with high levels of naturally occurring boron. Samples were taken of tap and bottled water (173 and 22, respectively), as well as urine from 22 volunteers, and subsequently analyzed by inductively coupled plasma spectroscopy (ICP-OES). Boron varied in public tap water from 0.22 to 11.3mgL(-1), with a median value of 2.9mgL(-1), while concentrations of boron in bottled water varied from 0.01 to 12.2mgL(-1). Neither tap nor bottled water samples had concentrations of boron within WHO recommended limits. The concentration of boron in urine varied between 0.45 and 17.4mgL(-1), with a median of 4.28mgL(-1) and was found to be correlated with tap water sampled from the homes of the volunteers (r=0.64). Authors highly recommend that in northern Chile - where levels of boron are naturally high - that the tap and bottled water supplies be monitored in order to protect public health and that regulatory standards also be established for boron in drinking water in order to limit exposure.

Can environmental or occupational hazards alter the sex ratio at birth? A systematic review

More than 100 studies have examined whether environmental or occupational exposures of parents affect the sex ratio of their offspring at birth. For this review, we searched Medline and Web of Science using the terms ‘sex ratio at birth’ and ‘sex ratio and exposure’ for all dates, and reviewed bibliographies of relevant studies to find additional articles. This review focuses on exposures that have been the subject of at least four studies including polychlorinated biphenyls (PCBs), dioxins, pesticides, lead and other metals, radiation, boron, and g-forces. For paternal exposures, only dioxins and PCBs were consistently associated with sex ratios higher or lower than the expected 1.06. Dioxins were associated with a decreased proportion of male births, whereas PCBs were associated with an increased proportion of male births. There was limited evidence for a decrease in the proportion of male births after paternal exposure to DBCP, lead, methylmercury, non-ionizing radiation, ionizing radiation treatment for childhood cancer, boron, or g-forces. Few studies have found higher or lower sex ratios associated with maternal exposures. Studies in humans and animals have found a reduction in the number of male births associated with lower male fertility, but the mechanism by which environmental hazards might change the sex ratio has not yet been established.

Removal of selected nuisance anions by Octolig

Octolig, a commercially available immobilized ligand (IMLIG), has been studied for its effectiveness in removing nuisance anions. The material consists of polyethylenediamines covalently linked to high surface-area silica, and has a high affinity for transition metal ions. Previous research indicated that anions could be removed quantitatively from aqueous solutions using the metal derivatives of Octolig as packing in column chromatography. The present study focused on the results with Octolig alone. Quantitative removals (> 99%) were obtained for arsenate, chromate, paramolybdate, selenious acid, and fluoride. Boric acid was not removed by under similar conditions, but previously the copper(II) derivative of Octolig had been partially successful. A mechanism of removal is proposed.

Estimation of human daily boron exposure in a boron-rich area

Although, the safe limits of human daily boron (B) exposure are not absolutely clear, there is a growing interest in B and its effects on human health. The aim of the present study was to estimate daily B exposure in 66 males in Turkey living in a B-rich area using water containing at least 2 mg/l boron, with an average age of 38·55 (se 1·66) years and an average number of years of residence in the B-rich area of 35·89 (se 1·73). Another group of males (n 57), living in the city centres of Balıkesir and Ankara, were taken as controls; the average age and number of years of residence for this group were 29·44 (se 1·43) and 10·26 (se 1·83) years, respectively. As it is assumed that the B level in urine reflects daily B exposure, the amount of urinary B of both the study and control groups was analysed by using an inductively coupled plasma optical emission spectrometry (ICP-OES) technique. The average daily B exposure value was calculated as 6·77 (se 0·47) mg in the study group and 1·26 (se 0·1) mg in the controls. The results of this study are expected to contribute to creating a reference value for a safe daily B exposure.