Ni In Urine Research Articles

The effect of particle size on oral bioavailability and bioaccessibility of soil Ni from different sources

The goal of the work was to contribute to a unified approach to assessing the risk to human health of soil ingestion, for contaminated sites with elevated [Ni]. Robust relationships between in vitro bioaccessibility and in vivo bioavailability of Ni in various soils, with mechanistic understanding, would enable site-specific assessments of human exposure through soil ingestion. Four soils (three ultramafic Brunisols with geogenic Ni and one Organic soil with anthropogenic Ni) were sieved into PS < 10 μm, 10–41 μm, 41–70 μm, 70–105 μm, 105–150 μm, and 150–250 μm, the [Ni]T for which ranged from 560 to 103000 mg/kg. Mass fraction-adjusted [Ni]IVBA (SBRC gastric) for each soil fraction was similar whether calculated for all particles <250 μm or <150 μm %NiIVBA ranged from 3% to 16% of [Ni]T and %NiABA (accumulated Ni in urine, kidneys, and small intestine of Sprague Dawley rats gavaged with a soil) ranged from 0% to 0.49%. The correlation between these two measurements was weak (R2 = 0.06). Multiple linear dose response relationships attributing variation in %NiABA to %NiIVBA plus soil physicochemical parameters known to influence trace element availability in soils were developed. As many soil properties measured in this study were highly correlated, ridge regression enabled a predictive relationship where the effect of each parameter was its true contribution to variation in %NiABA. Using a ridge constant (k) of 0.012, %NiABA could be predicted from %NiIVBA adjusted for soil absorptive entities (OrgC, and Fe oxides (negative coefficients)) and soil pH (positive coefficient). %NiABA predicted from this relationship was very close to 1:1 with the observed %NiABA except at the lowest observed values which were lower than predicted. This study shows that as the conditions increasingly favour soil Ni solubility, more of the Ni was bioavailable; this generalization was true regardless of particle size or soil origin.

The relatively higher concentrations of trace elements to arsenic may have influenced on methylation process of inorg- As in humans

The relatively higher concentrations of trace elements to arsenic may have influenced on methylation process of inorg- As in humans

Metal Exposure from E-Cigarette Users in Maryland

BackgroundAs more is known about the components of electronic cigarettes (e-cigarettes), it is important to characterize metal exposure from use. Nickel (Ni) and chromium (Cr) are frequent components of e-cigarette heating coils and have been found in e-liquid and aerosol. We compared Ni and Cr biomarker concentrations among Maryland e-cigarette users to that of non-e-cigarette users/non-smokers, and also assessed the association of e-cigarette use patterns with metal biomarker concentrations.MethodsWe recruited 50 e-cigarette users and 50 non-e-cigarette users from March to October 2017. Data were collected on health status, e-cigarette use patterns, device characteristics, sociodemographic factors. Urine, saliva, and exhaled breath condensate (EBC) samples were collected. Metal concentrations were measured using ICP-MS.ResultsThe median Cr concentrations for non-users and e-cigarette users were 0.92 and 1.77 &amp;#956;g/l in urine, 0.62 and 0.73 &amp;#956;g/l in saliva, and both 0.14 &amp;#956;g/l in EBC, respectively; median Ni concentrations were 0.68 and 1.11 &amp;#956;g/l in urine, 0.27 and 0.55 &amp;#956;g/l in saliva, and both 0.13 &amp;#956;g/l in EBC. Compared to non-users, e-cigarette users had significantly higher levels of Ni concentration in urine (GMR 3.99, 95% CI: 1.95-8.19, p &amp;lt; 0.001). Increased urine Ni concentrations were observed among users who vaped at a higher voltage (3.65-4.20 volts) and used a higher nicotine concentration (12-24 mg/ml). Saliva Cr concentrations were increased with more e-liquid consumed per week (35 to 60 ml). Both Ni and Cr saliva concentrations were increased among users that changed their coils more frequently (&amp;gt;2/month).ConclusionE-cigarette users had significantly higher levels of Cr in urine than non-users. Ni in urine and Cr in saliva were positively associated with higher e-cigarette use and voltage. Increased metal concentrations in saliva associated with more frequent coil change provide an indication that instructions and best practice of using coils is warranted.

Prevalence of nickel sensitization and urinary nickel content of children are increased by nickel in ambient air

In a cross-sectional study performed in 2000, an unexpected positive association between nickel (Ni) in ambient air, urinary Ni content and the prevalence of Ni sensitization in a subgroup of 6-yr-old children living near a steel mill was observed. Between 2005 and 2006, in a different and larger study population, we examined if Ni from ambient air or urinary Ni concentration was related to Ni sensitization in children living next to Ni-emitting steel mills. We studied 749 school beginners living in four Ni-polluted industrial areas of North Rhine-Westphalia, Germany. We assessed Ni in ambient air, Ni in urine from children and mothers, and Ni in tap water, conducted patch tests in children (including the NiSO 4-dilution test) and collected questionnaire data. Statistics were done by linear and logistic regression analyses, adjusted for covariates. At increased Ni concentration in ambient air (unit of increase: 10 ng/m 3), urinary Ni concentrations rose in both mothers (9.1%; 95% CI: 6.8–11.4%) and children (2.4%; 95% CI: 0.4–4.4%). The prevalence of Ni sensitization in children was associated with increased Ni from ambient air (unit of increase: 18 ng/m 3; odds ratio 1.28; 95% CI: 1.25–1.32) and urinary Ni concentration (unit of increase: 7.1 μg/L; odds ratio 2.4; 95% CI: 1.20–4.48). Ni in ambient air of areas with Ni-emitting factories contributes to internal Ni exposure in residents via inhalation and, furthermore, is a risk factor for the development of Ni sensitization in children.

Urinary elimination of nickel and cobalt in relation to airborne nickel and cobalt exposures in a battery plant

To estimate the relationship between Ni concentrations in the ambient air and in the urine, at a battery plant using nickel hydroxide. Workers occupationally exposed to a mixture of nickel hydroxide, metallic cobalt and cobalt oxyhydroxide dust were studied during two consecutive workdays. Air levels of Ni and Co in total dust were determined by personal sampling in the breathing zone. Both metals in air were sampled by Teflon binder filters and analyzed by inductively coupled plasma absorption emission spectrophotometry. Urine was collected from 16 workers immediately before and after the work shift. Urinary Ni and Co concentrations were measured by electrothermal atomic absorption spectrometry. A poor correlation was seen between Co in the air and in post-shift urine (r = 0.491; P < 0.01), and no correlation was found between Ni in the air and in post-shift urine (r = 0.272; P = 0.15), probably due to the use of respiratory protection. The subjects were exposed to higher levels of Ni than Co (Ni (mg/m(3)) = -0.02 + 7.41 Co (mg/m(3)), r = 0.979, P < 0.0001). Thus, exposure to Co at 0.1 mg/m(3) should produce a Ni level of 0.7 mg/m(3). According to section XIII of the German list of MAK and BAT Values, a relationship between exposure to Co and urinary Co excretion, Co (microg/l) = 600 Co (mg/m(3)), has been established and the relationship between soluble or insoluble Ni salts in the air and Ni in urine was as follows: Ni (microg/l) = 10 + 600 Ni (mg/m(3)) or Ni (microg/l) = 7.5 + 75 Ni (mg/m(3)). Assuming nickel hydroxide to be soluble and to be insoluble, the Ni concentrations corresponding to Ni exposure at 0.7 mg/m(3) were calculated as 430 and 60 microg Ni/l, respectively. Similarly, exposure to Co at 0.1 mg/m(3) should result in Co urinary concentrations of 60 microg Co/l. On the other hand, a good correlation was found between Co and Ni in post-shift urine (Ni (microg/l) = 9.9 + 0.343 Co (microg/l), r = 0.833, P < 0.0001). On the basis of this relationship, the corresponding value found in our study was 0.343 x 60 microg Co/l + 9.9 = 30.5 microg Ni/l. This value was close to that calculated by the equation for a group of insoluble compounds, but about 14 times lower than that calculated by the equation for a group of soluble compounds. Our results suggest that exposure to nickel hydroxide yields lower urine nickel concentrations than the very soluble nickel salts, and that the grouping of nickel hydroxide might be reevaluated. Therefore, to evaluate conclusively the relationship between nickel hydroxide dust in the air and Ni in post-shift urine, further studies are necessary.

Monitoring of chromium and nickel in biological fluids of grinders grinding stainless steel

Stainless steel (SS) welders usually spend some of their working time grinding, to finish and smoothen the welding groove. The aim of this study was to investigate possible relations between the concentrations of nickel (Ni) and chromium (Cr) in the work atmosphere generated by grinders grinding SS, and to compare the air levels to the levels of Cr and Ni in their biological fluids. Hereby, it might be possible to identify the contribution of grinding to the levels of Cr and Ni in biological fluids in SS welders. Also the airborne levels of Cr and Ni in SS grinders were compared to corresponding levels in SS welders. The subjects examined in this study were selected among SS grinders not performing welding. Nine grinders were monitored for 1 workweek, measuring Cr and Ni in air, blood and urine. They were questioned about their exposure to Cr and Ni during their working careers. Air levels of total Cr up to 95 microg/m(3) and Ni levels up to 25 microg/m(3) were measured. Chromium(VI) (Cr(VI)) was detectable only in five air samples; the levels in the remaining samples were below the detection limit. The levels of Cr in blood and urine were also low. The levels of Ni in urine were close to those for MMA and MIG/MAG SS welders. In spite of high levels of total Cr and Ni observed in air, the levels found in biological fluids were low. The Cr levels in more than 50% of the whole blood and red cell samples and about 1/3 of the Cr-plasma levels were below the detection limits. The mean blood levels for Cr were 0.43, 0.60 and 0.35 microg/l, in whole blood, plasma and red cells, respectively. The mean levels for Cr in the urine was 1.6, 1.4 and 1.4 microg/g creatinine for the first void, just before and just after work. For Ni the mean blood levels were 0.87 microg/l in whole blood and 0.68 microg/l in plasma. The mean levels and ranges of Ni from the first void, just before and after work in urine were 3.79 microg/g creatinine, 3.39 and 4.56, respectively. The Cr concentrations found in whole blood, plasma and red cells were approximately the same as those found in the unexposed controls and among TIG SS welders, while the urinary levels were somewhat higher, but still lower than in the welders applying other welding techniques. The mean levels of Ni in the urine of grinders were higher than those of welders, except for SS welders welding the MIG/MAG-method. SS Grinding seems not to contribute significantly to the uptake of Cr, which may be explained by the fact that most of Cr in the air is present in the metallic (0-valent) or trivalent form, and hardly any as Cr(VI), and therefore hardly being taken up in the airways. The grinders' uptake of Ni seems to take place to the same extent as in SS welders.

Reference values for cobalt, copper, manganese, and nickel in urine among women of the general population in Japan

The present study was initiated to establish the reference levels of Co, Cu, Mn, and Ni in urine of women in the general Japanese population. Stored urine samples were subjected to the analysis. The samples were collected from 1,000 adult women all over Japan, who had no occupational exposure to these elements. Co, Cu, Mn, and Ni in urine were analyzed by graphite furnace atomic absorption spectrometry. The concentrations were distributed log-normally, and were presented in terms of geometric mean (GM) and geometric standard deviation, as observed or after correction for creatinine concentration or a specific gravity of urine of 1.016. The GM values of observed levels (i.e., with no correction for urine density) and of the levels after correction for creatinine (cr) concentration (values in parenthesis) were 0.68 g/l (0.60 microg/g cr) for Co, 13.4 g/l (11.8 g/g cr) for Cu, 0.14 microg/l (0.12 g/g cr) for Mn and 2.1 g/l (1.8 g/g cr) for Ni. There was a life-long age-dependent increase in Cu. Mn levels reached the maximum at 60 to 69 years of ages. In contrast, age-dependency was not substantial in Co and Ni. Comparison with values reported in literatures for other areas showed that Co and Ni levels in urine of Japanese women are higher than, Cu level is comparable with, and Mn level is lower than others. The reasons for high Co and Ni levels deserve further study.

P1106 日本人女性尿中コバルト、銅、マンガンとニッケルの参照値および加齢変化(一般演題:ポスター,地方の時代の産業保健,第79回日本産業衛生学会)

P1106 日本人女性尿中コバルト、銅、マンガンとニッケルの参照値および加齢変化(一般演題:ポスター,地方の時代の産業保健,第79回日本産業衛生学会)

Monitoring of chromium and nickel in biological fluids of stainless steel welders using the flux-cored-wire (FCW) welding method

This study was undertaken to investigate the exposure to chromium (Cr) and nickel (Ni) in flux-cored wire (FCW) welders welding on stainless steel (SS). Seven FCW welders were monitored for 3 days to 1 workweek, measuring Cr and Ni in air, blood, and urine. The welders were questioned about exposure to Cr and Ni during their whole working careers, with emphasis on the week of monitoring, about the use of personal protective equipment and their smoking habits. The air concentrations were mean 200 microg/m(3) (range 2.4-2,744) for total Cr, 11.3 microg/m(3) (<0.2-151.3) for Cr(VI), and 50.4 microg/m(3) (<2.0-416.7) for Ni during the workdays for the five welders who were monitored with air measurements. The levels of Cr and Ni in biological fluids varied between different workplaces. For Cr in whole blood, plasma, and erythrocytes, the mean levels after work were 1.25 (<0.4-8.3) and 1.68 (<0.2-8.0) and 0.9 (<0.4-7.2) microg/l, respectively. For Ni most of the measurements in whole blood and plasma were below the detection limits, the mean levels after work being 0.84 (<0.8-3.3) and 0.57 microg/l (<0.4-1.7), respectively. Mean levels for Cr and Ni in the urine after work were 3.96 (0.34-40.7) and 2.50 (0.56-5.0) microg/g creatinine, respectively. Correlations between the Cr(VI) levels measured in air and the levels of total Cr in the measured biological fluids were found. The results seem to support the view that monitoring of Cr in the urine may be versatile for indirect monitoring of the Cr(VI) air level in FCW welders. The results seem to suggest that external and internal exposure to Cr and Ni in FCW welders welding SS is low in general.

A comparison of Inductively Coupled Plasma Mass Spectrometry with Electrothermal Atomic Absorption Spectrophotometry for the Determination of Trace Elements in Blood and Urine from non Occupationally Exposed Populations

Quadrupole Inductively coupled plasma mass spectrometric (QICP-MS) and electrothermal atomic absorption spectrophotometric (ETAAS) methods for the determination of Pb and Cd in whole blood and Al, Cd, Co and Ni in urine were compared. Simple sample pretreatments were used for both instrumental techniques. Urine samples were diluted with either Millipore water or dilute HNO3, while blood samples were diluted with a solution containing either 0.14M NH3 or 0.03 M NH3, 0.05% EDTA and 0.05% Triton X-100 in Millipore water. Scandium, yttrium and indium were used as internal standards for ICP-MS measurements and (NH4)2HPO4 as a chemical modifier for the determination of Pb and Cd by ETAAS. For ICP-MS analysis, pneumatic nebulization was used for introduction of urine samples and flow injection for introduction of blood samples. Matrix matched standards were used for all calibrations and methods were validated by analyzing reference materials and samples from external quality assurance programmes. Concentrations of the listed metals were determined in blood and urine samples obtained from a healthy non occupationally exposed population and reference samples, using both instrumental techniques. The study group (n = 90) was randomly selected from a study population (n = 220) recruited from three regions considered representative of the environment encountered by the majority of the United Kingdom population. Males and females were equally represented and ranged in age from 17-65 yrs. The correlation between results obtained by the two techniques was good for all elements measured, ranging from r = 0.88 for Co in urine to r = 0.99 for both Pb and Cd in blood.

Investigation of professional nickel exposure in nickel refinery workers

For assessing the real exposure level of nickel in electrolytical nickel production workers we monitored the following indicators of Ni load. (a) Stationary air sampling of Ni, (b) personal air sampling of Ni, (c) urine Ni excretion determined on group basis, (d) the 4 hours specimen of Ni excretion determined on an individual basis. A tentative limit for Ni in urine, roughly corresponding to the MAC 0.05 mg/m 3 was 12 μg/l Ni according to (c) and 30 μg/l Ni according to (d). The occupational exposure limit for Ni in urine accepted in Czechoslovakia is 30 μg/l Ni.

Discrete nebulization using aerosol deposition in electrothermal vaporization for inductively coupled plasma-atomic emission spectrometry

Discrete nebulization using aerosol deposition is examined as a procedure for sample introduction in electrothermal vaporization for ICP-AES. Small volumes of solution (< 50 μl) may be introduced into a pneumatic nebulizer manually from a Teflon microsampling device or Teflon funnel, or automatically by a flame autosampler system. The analyte aerosol is deposited under controlled conditions on the surface of a graphite platform. Optimum operating conditions were established, and the performance of the combination is demonstrated by the direct determination of Cr, Cu and Ni in urine. The method offers good precision (< 3%), reduction or even elimination of matrix interferences, and microsampling capabilities.