Boron Abstracts 3

© 2013

Boron in Human Nutrition and its Regulations Use

         (Dinca and Scorei 2013) Download

According to the literature, there are increasingly more scientific data regarding the boron importance in the human nutrition. The request for boron supplements has become more significant due to the following two discoveries: boron transport within the animal cell and the cellular signaling of some bacteria by a sugar borate complex. It is necessary to establish the benefits and the toxicity of boron consumption for humans and animals, although a biological function of boron has not been defined yet. In addition, it is important to know the legal regulations for boron use worldwide, its physiological effects and health uses.

Plasma boron and the effects of boron supplementation in males

         (Green and Ferrando 1994) Download

Recently, a proliferation of athletic supplements has been marketed touting boron as an ergogenic aid capable of increasing testosterone. The effect of boron supplementation was investigated in male bodybuilders. Ten male bodybuilders (aged 20 to 26) were given a 2.5-mg boron supplement, while nine male bodybuilders (aged 21 to 27) were given a placebo for 7 weeks. Plasma total and free testosterone, plasma boron, lean body mass, and strength measurements were determined on day 1 and day 49 of the study. A microwave digestion procedure followed by inductively coupled argon plasma spectroscopy was used for boron determination. Twelve subjects had boron values at or above the detection limit with median value of 25 ng/ml (16 ng/ml lower quartile and 33 ng/ml upper quartile). Of the ten subjects receiving boron supplements, six had an increase in their plasma boron. Analysis of variance indicated no significant effect of boron supplementation on any of the other dependent variables. Both groups demonstrated significant increases in total testosterone (p < 0.01), lean body mass (p < 0.01), and one repetition maximum (RM) squat (p < 0.001) and one RM bench press (p < 0.01). The findings suggest that 7 weeks of bodybuilding can increase total testosterone, lean body mass, and strength in lesser-trained bodybuilders, but boron supplementation affects these variables not at all.

Effects of chronic boron exposure on semen profile

         (Korkmaz, Yenigun et al. 2011) Download

The possible changes in semen quality were studied in men living in a boron mining area. The subjects in the boron group had exposure to boron at an average level of 6.5 mg/day, as determined by urinary analysis. The results obtained by the boron group were compared to those obtained for the control group whose subjects were living in the same geographical area but away from the boron region; average exposure level was 1.4 mg/day for this group. The semen samples were analyzed according to the recommendations of the World Health Organization. Boron levels were established in the water samples obtained from various locations in the study region. In the boron mining fields where the subjects in the boron group live, water samples contained boron in the range of 1.4-6.5 mg/L, while the values were <0.01 mg/L for the water samples obtained from the region where the subjects of the control group reside. No negative effects were found in the sperm samples obtained from the subjects of the boron group.

Prevalence of prostate cancer in high boron-exposed population: a community-based study

         (Muezzinoglu, Korkmaz et al. 2011) Download

We investigated the possible relationship between boron exposure and prostate cancer (PCa) for men living and being employed at boron mines in villages with rich boron minerals. Out of 456 men studied, 159 were from villages with rich boron sources and boron levels in drinking water of >1 mg L(-1) and these men formed the study group, while 63 from villages with rich boron sources and boron levels in drinking water of <1 mg L(-1) were enrolled into control group 1. A further 234 subjects from other villages with no boron mines were considered as control group 2. Prostate specific antigen (PSA) levels could be obtained from a total of 423 men. Urinary boron concentration as an indicator of boron exposure in 63 subjects, prostatic volumes by transrectal ultrasonography in 39 subjects, and prostatic biopsies in 36 subjects were obtained for study and control groups. The daily boron exposure was calculated according to urinary boron levels. Although there was no significant difference among the groups in terms of total PSA levels, the number of subjects with tPSA >/=2.5 and tPSA >/=10.0 ng dL(-1) prostatic volumes in men whose prostates were biopsied (p < 0.012) was significantly lower in the study group as compared with those in the control group 2. These results suggested that high exposure to boron might have an implication within the prostatic cellular processes related to hyperplasia and carcinogenesis, even though we did not find a statistically significant association between PCa and boron exposure.

The effect of boron supplementation on the distribution of boron

         (Naghii and Samman 1996) Download

Boron has been shown to increase the concentration of oestrogen and testosterone in plasma. The aim of this study was to investigate further the effect of boron by determining the response to three levels of boron intake during an experimental period of 6 weeks. The concentration of plasma testosterone and its production in the testes were determined in addition to the distribution of boron in selected tissues. Boron was added to the drinking water as boric acid to provide 2, 12.5, and 25 mg boron/rat/d. Body weight gain was found to be higher at the lowest dose but no significant change was observed at the highest dose. The distribution of boron in all tissues reflected its level of intake with all tissues demonstrating an increase over time. Within 6 weeks, rats fed the lowest and intermediate doses appeared to have a favorable effect on the indices examined, whereas the toxic testicular effects indicated by significant increases in the plasma follicle stimulating hormone concentration and testicular atrophy was associated with the higher dose (25 mg). The synthesis of testosterone by the testicular homogenates in vitro from its immediate precursor, androstenedione in the presence of boron was determined, but there did not appear to be any clear relationship between dietary boron and testosterone production in vitro. The effect of boron on steroidogenesis and testicular function and development appears to be proportional to the dose and subsequent boron concentration in the testes. (J. Nutr. Biochem. 7:507-512, 1996.)

Essentiality of boron for healthy bones and joints

         (Newnham 1994) Download

Since 1963, evidence has accumulated that suggests boron is a safe and effective treatment for some forms of arthritis. The initial evidence was that boron supplementation alleviated arthritic pain and discomfort of the author. This was followed by findings from numerous other observations epidemiologic and controlled animal and human experiments. These findings included a) analytical evidence of lower boron concentrations in femur heads, bones, and synovial fluid from people with arthritis than from those without this disorder; b) observation evidence that bones of patients using boron supplements are much harder to cut than those of patients not using supplements; c) epidemiologic evidence that in areas of the world where boron intakes usually are 1.0 mg or less/day the estimated incidence of arthritis ranges from 20 to 70%, whereas in areas of the world where boron intakes are usually 3 to 10 mg, the estimated incidence of arthritis ranges from 0 to 10%; d) experimental evidence that rats with induced arthritis benefit from orally or intraperitoneally administered boron; e) experimental evidence from a double-blind placebo-boron supplementation trial with 20 subjects with osteoarthritis. A significant favorable response to a 6 mg boron/day supplement was obtained; 50% of subjects receiving the supplement improved compared to only 10% receiving the placebo. The preceding data indicate that boron is an essential nutrient for healthy bones and joints, and that further research into the use of boron for the treatment or prevention of arthritis is warranted.

The saga of boron in food: From a banished food preservative to a beneficial nutrient for humans

         (Nielsen 1991) Download

Boron enhances and mimics some of the effects of estrogen therapy in postmenopausal women

         (Nielsen, Gallagher et al. 1992) Download

Facts and fallacies about boron

         (Nielsen 1992) Download


Chronic boron exposure and human semen parameters

         (Robbins, Xun et al. 2010) Download

Boron found as borates in soil, food, and water has important industrial and medical applications. A panel reviewing NTP reproductive toxicants identified boric acid as high priority for occupational studies to determine safe versus adverse reproductive effects. To address this, we collected boron exposure/dose measures in workplace inhalable dust, dietary food/fluids, blood, semen, and urine from boron workers and two comparison worker groups (n=192) over three months and determined correlations between boron and semen parameters (total sperm count, sperm concentration, motility, morphology, DNA breakage, apoptosis and aneuploidy). Blood boron averaged 499.2 ppb for boron workers, 96.1 and 47.9 ppb for workers from high and low environmental boron areas (p<0.0001). Boron concentrated in seminal fluid. No significant correlations were found between blood or urine boron and adverse semen parameters. Exposures did not reach those causing adverse effects published in animal toxicology work but exceeded those previously published for boron occupational groups.

An overview of male reproductive studies of boron with an emphasis on studies of highly exposed Chinese workers

         (Scialli, Bonde et al. 2010) Download

Boron treatment of rats, mice, and dogs has been associated with testicular toxicity, characterized by inhibited spermiation at lower dose levels and a reduction in epididymal sperm count at higher dose levels. The no-adverse-effect level for reproductive effects in male rats is 17.5mg B/kg bw/day. Earlier studies in human workers and populations have not identified adverse effects of boron exposure on fertility, but outcome measures in these studies were relatively insensitive, based mainly on family size and did not include an evaluation of semen end points. A recent study of nearly 1000 men working in boron (B) mining or processing in Liaoning province in northeast China has been published in several Chinese and a few English language papers. This study included individual assessment of boron exposure, interview data on reproductive experience and semen analysis. Employed men living in the same community and in a remote community were used as controls. Boron workers (n=75) had a mean daily boron intake of 31.3mg B/day, and a subset of 16 of these men, employed at a plant where there was heavy boron contamination of the water supply, had an estimated mean daily boron intake of 125 mg B/day. Estimates of mean daily boron intake in local community and remote background controls were 4.25mg B/day and 1.40 mg/day, respectively. Reproductive outcomes in the wives of 945 boron workers were not significantly different from outcomes in the wives of 249 background control men after adjustment for potential confounders. There were no statistically significant differences in semen characteristics between exposure groups, including in the highly exposed subset, except that sperm Y:X ratio was reduced in boron workers. Within exposure groups the Y:X ratio did not correlate with the boron concentration in blood, semen and urine. In conclusion, while boron has been shown to adversely affect male reproduction in laboratory animals, there is no clear evidence of male reproductive effects attributable to boron in studies of highly exposed workers.

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

         (Usuda, Kono et al. 2007) Download

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.Over the past decade we have successfully used inductively coupled plasma emission spectrometry for the determination of reference values for urinary concentrations of boron, lithium and strontium. Taking into account the short biological half-life of these elements and the fact that their major excretion route is via the kidney, urine was considered to be a suitable material for monitoring of exposure to these elements. We confirmed that urinary concentrations of boron, lithium and strontium follow a lognormal distribution. The geometric mean reference values and 95% confidence intervals were 798 mug/l (398-1599 mug/l) for boron, 23.5 mug/l (11.0-50.5 mug/l) for lithium and 143.9 mug/l (40.9-505.8 mug/l) for strontium. There were no discrepancies between our values and those previously reported. Our reference values and confidential intervals can be used as guidelines for the health screening of Japanese individuals to evaluate environmental or occupational exposure to these elements.


References

Dinca, L. and R. Scorei (2013). "Boron in Human Nutrition and its Regulations Use." Journal of Nutritional Therapeutics 2: 22-29. [PMID:

Green, N. R. and A. A. Ferrando (1994). "Plasma boron and the effects of boron supplementation in males." Environ Health Perspect 102 Suppl 7: 73-7. [PMID: 7889885]

Korkmaz, M., M. Yenigun, et al. (2011). "Effects of chronic boron exposure on semen profile." Biol Trace Elem Res 143(2): 738-50. [PMID: 21170602]

Muezzinoglu, T., M. Korkmaz, et al. (2011). "Prevalence of prostate cancer in high boron-exposed population: a community-based study." Biol Trace Elem Res 144(1-3): 49-57. [PMID: 21431327]

Naghii, M. R. and S. Samman (1996). "The effect of boron supplementation on the distribution of boron." Nutritional Biochemistry 7: 507-512. [PMID:

Newnham, R. E. (1994). "Essentiality of boron for healthy bones and joints." Environ Health Perspect 102 Suppl 7: 83-5. [PMID: 7889887]

Nielsen, F. H. (1991). "The saga of boron in food: From a banished food preservative to a beneficial nutrient for humans." Current Topics in Plant Biochemistry and Physiology 10: 274-286. [PMID:

Nielsen, F. H. (1992). "Facts and fallacies about boron." Nutrition Today May/June. [PMID:

Nielsen, F. H., S. K. Gallagher, et al. (1992). "Boron enhances and mimics some of the effects of estrogen therapy in postmenopausal women." J Trace Elem Exp Med 5: 237 -246. [PMID:

Robbins, W. A., L. Xun, et al. (2010). "Chronic boron exposure and human semen parameters." Reprod Toxicol 29(2): 184-90. [PMID: 19962437]

Scialli, A. R., J. P. Bonde, et al. (2010). "An overview of male reproductive studies of boron with an emphasis on studies of highly exposed Chinese workers." Reprod Toxicol 29(1): 10-24. [PMID: 19850122]

Usuda, K., K. Kono, et al. (2007). "An overview of boron, lithium, and strontium in human health and profiles of these elements in urine of Japanese." Environ Health Prev Med 12(6): 231-7. [PMID: 21432068]