[Challenges and solutions in immigrant occupational health in the United States: a literature review and comparative analysis].

Objectives: Because of the declining birthrate in Japan, an increasing number of companies are hiring immigrants to fill the labor shortage. Although research on migrant occupational health has progressed in the United States, this topic has received little attention in Japan. The aim of this study was to elucidate the current situation, challenges, and solutions surrounding the occupational health of immigrant workers in the United States.

Risk Assessment Study of Fluoride Salts: Probability-Impact Matrix of Renal and Hepatic Toxicity Markers.

The present risk assessment study of fluoride salts was conducted by oral administration of three different doses of sodium and potassium fluorides (NaF, KF) and zinc fluoride tetrahydrate (ZnF2 •4H2O) to male Wistar rats. The rats were divided into control and nine experimental groups, to which oral injections of 0.5 mL distilled water and 0.

Comparison of the Biological Impacts of the Fluoride Compounds by Graphical Risk Visualization Map Technique.

Various fluoride compounds are widely used in industry. The present risk assessment study was conducted using a series of inorganic binary fluorides of the type XFn, where X(n) = Na(+), K(+), Li(+), Mg(2+), Ca(2+), Sr(2+), Ba(2+), Al(3+), Nd(3+), La(3+), Ce(3+), Sm(3+), Gd(3+), Y(3+), Yb(2+), and Zn(2+). The aqueous solutions of these salts were orally administrated to 16 experimental groups (one for each of the salts tested).

Risk assessment visualization of rubidium compounds: comparison of renal and hepatic toxicities, in vivo.

Rubidium has been considered to be nontoxic. Its use includes thin film on glass deposition and as medical contrast medium. Recent technology innovations also involve the use of rubidium, but there is limited information about the biological effects of its various compounds.

Urinary monitoring of exposure to yttrium, scandium, and europium in male Wistar rats.

On the assumption that rare earth elements (REEs) are nontoxic, they are being utilized as replacements of toxic heavy metals in novel technological applications. However, REEs are not entirely innocuous, and their impact on health is still uncertain. In the past decade, our laboratory has studied the urinary excretion of REEs in male Wistar rats given chlorides of europium, scandium, and yttrium solutions by one-shot intraperitoneal injection or oral dose.

[Systematic training for occupational physicians in schools of public health in the US and its application to Japan's system--Master of Public Health Program at Harvard School of Public Health].

Objectives And Results: Globalization has progressed tremendously resulting in far-reaching changes in the work environment. In Japan, occupational health and safety (OSH) activities are performed under and improved by regulations. However, this system is not likely to satisfy the unceasing diversification of social demand for OSH in recent years.

Distribution, elimination, and renal effects of single oral doses of europium in rats.

Single doses of europium (III) chloride hexahydrate were orally administered to several groups of rats. Cumulative urine samples were taken at 0-24 h, and blood samples were drawn after 24-h administration. The europium concentration was determined in these samples by inductively coupled plasma atomic emission spectroscopy.

Toxicological aspects of cadmium and occupational health activities to prevent workplace exposure in Japan: A narrative review.

Chemicals are an essential part of modern manufacture processes. Their use must be managed with great attention in occupational settings to avoid serious detrimental effects to the health of employees. For example, cadmium compounds are indispensable for the production of nickel-cadmium rechargeable batteries or as chemical stabilizer in plastics.

Effects of sodium monofluoroacetate on glucose, amino-acid, and fatty-acid metabolism and risk assessment of glucose supplementation.

Sodium monofluoroacetate (SMFA; also known as compound 1080) is a highly toxic chemical; therefore, accidental exposure and intentional misuse are of great concern. SMFA intoxication is reportedly caused by the inhibition of aconitase. However, the pathogenesis underlying SMFA intoxication is not clear.

Urinary scandium as predictor of exposure: effects of scandium chloride hexahydrate on renal function in rats.

Some of the rare earth elements such as Sc are believed to be non-toxic and, at present, are widely utilized for the replacement of toxic heavy metals in technological applications, but they are not entirely free of toxicity, with hidden potential health risks. In this animal experiment, we report the urinary scandium (Sc) excretion rate and nephrotoxiciy in male Wistar rats. For this purpose, the rats were given a single dose of a solution of scandium chloride by intraperitoneal injection.

X-ray fluorescence measurement of bone calcium, phosphorous and fluoride in a rat osteoporosis model.

The fluoride (F), calcium (Ca) and phosphorous (P) content in two parts of the bone mandible, lumbar spine and femur of rats fed a low mineral diet and corresponding controls were determined by X-ray fluorescence. The anterior part of the mandible, including teeth was labeled as part I while the posterior part, including the mandibular head but excluding the teeth was designed as part II. The bone Ca, P and F content of part I was the same for the experimental and control groups.

An overview of boron, lithium, and strontium in human health and profiles of these elements in urine of Japanese.

The biological, medical and environmental roles of trace elements have attracted considerable attention over the years. In spite of their relevance in nutritional, occupational and toxicological aspects, there is still a lack of consistent and reliable measurement techniques and reliable information on reference values. In this review our understandings of the urinary profilings of boron, lithium and strontium are summarized and fundamental results obtained in our laboratory are discussed.

Factors associated with good self-rated health of non-disabled elderly living alone in Japan: a cross-sectional study.

Background: Self-rated health (SRH) is reported as a reliable predictor of disability and mortality in the aged population and has been studied worldwide to enhance the quality of life of the elderly. Nowadays, the elderly living alone, a particular population at great risk of suffering physical and mental health problems, is increasing rapidly in Japan and could potentially make up the majority of the aged population. However, few data are available pertaining to SRH of this population.

Urinary fluoride reference values determined by a fluoride ion selective electrode.

As fluoride has a very short half-life in the body and the major route for fluoride excretion is via the kidney, human exposure is best measured in urine, where the concentration is expected to be highest. The urinary fluoride concentrations of 167 healthy Japanese adults were determined by means of a fluoride ion selective electrode. When the results were corrected for a specific gravity rho = 1.

Harmful effects and acute lethal toxicity of intravenous administration of low concentrations of hydrofluoric acid in rats.

The acute toxicity of hydrofluoric acid (HFA) was investigated in a 24-h lethal dose study of intravenous infusion in rats. The lethal dose lowest (LDLo) and LD50 were 13.1 and 17.

[Predictors of houseboundedness among elderly persons living autonomously in a rural community].

Aim: The housebound state is a risk factor for disability. This prospective study aimed to determine factors predictive of houseboundedness in the elderly, with an ultimate goal of preventing this condition.

Methods: A self-report questionnaire pertaining to mental, physical and social status was administered to 732 community-dwelling elderly persons (313 men, 419 women; age range, 65-85 years) in October 2000.

Urinary yttrium excretion and effects of yttrium chloride on renal function in rats.

Evaluation of yttrium exposure in biological samples has not been fully examined. To evaluate yttrium nephrotoxicity, yttrium chloride was orally administered to male Wistar rats and the urine volume (UV) and N-acetyl-beta-D-glucosaminidase (NAG) and creatinine excretion (Crt) were measured in 24-h urine samples. The urinary yttrium concentration and excretion rate were determined by inductively coupled plasma-argon emission spectrometry (ICP-AES).

Survey of strontium in mineral waters sold in Japan: relations of strontium to other minerals and evaluation of mineral water as a possible dietary source of strontium.

The concentrations of strontium, calcium, and magnesium in 33 brands of natural mineral waters commercially available in Japan were determined by inductively coupled plasma-atomic emission spectrometry. The geometric mean values were 94.4 microg/L for strontium, 19.

Urinary and serum titanium: assessment as an indicator of exposure to ammonium citratoperoxotitanate (IV) and its influence on renal function.

Ammonium citratoperoxotitanate IV (TAS-FINE) is a water-soluble titanium complex used to synthesize a photocatalytic titanium(IV) oxide film. This study was aimed to investigate the LD50, dose-response, time-course response, and renal toxicity of TAS-FINE using an animal model. Serum titanium (S-Ti) and its 24-h urinary excretion (U-Ti) were determined by inductively coupled plasma-argon emission spectrometry (ICPAES) after a single oral TAS-FINE administration to male Wistar rats.

Determination of reference concentrations of strontium in urine by inductively coupled plasma atomic emission spectrometry.

Objective: The aim of this study was to establish reference concentrations of urinary strontium by inductively coupled plasma atomic emission spectrometry (ICP-AES).

Methods: For the determination of strontium, urine samples were collected from healthy Japanese (n=146; 115 males, 31 females; mean age, 33±9 years; age range, 18 to 58 years). The urine samples stored at or below -20°C were thawed with incubation at 40°C for 30 min and sediments were dissolved by vigorous shakings.

Urinary nickel: measurement of exposure by inductively coupled plasma argon emission spectrometry.

Nickel is a rare earth metal and is widely used in modern industry. Its overexposure in human beings can provoke significant effects including lung, cardiovascular and kidney diseases. As an index of occupational exposure, urine is widely used for the monitoring of nickel concentration because it is a minimally invasive method.

Markers of cadmium exposure in workers in a cadmium pigment factory after changes in the exposure conditions.

The objective of this study was to assess changes in concentrations of cadmium in the blood (Cd-B), cadmium in the urine (Cd-U), beta2-microglobulin in the serum (beta2-mG-S) and beta2-microglobulin in the urine (beta2-mG-U) of workers at a cadmium (Cd) pigment factory in Japan in which exposure conditions improved. We evaluated reversibility of these markers in continuously employed workers in relation to changes in exposure levels resulting from improvements in the workplace and the reduced production of Cd. Our study involved both environmental and biological monitoring.

Systemic effects and skin injury after experimental dermal exposure to monochloroacetic acid.

There have been many fatal occupational accidents of skin exposure to monochloroacetic acid (MCA). However, there have been no reports of dermatological findings and the lethal consequences have not yet been demonstrated. Therefore, harmful local and systemic effects were investigated after dermal exposure to MCA.

Lethal inhalation exposure during maintenance operation of a hydrogen fluoride liquefying tank.

Calcium sulfate adheres to the inside of liquefying pipes during the production of liquefied hydrogen fluoride. It is regularly washed away with water jets every six months. Two days before the operation, the pipes were experimentally washed down with water and the safety of the operation was confirmed with acidic washing fluid (pH 5).