Associations between welding fume exposure and blood hemostatic parameters among workers exposed to welding fumes in confined space in Chonburi, Thailand.

BACKGROUND: Occupational welding fumes contain varieties of toxic metal particles and may affect cardiovascular system like the Particulate Matters (PM). Few studies have focused on the effects of toxic metals on the hemodynamic balance; however, the reporting results were not consistent. This study aimed to investigate the association between toxic metals exposure (Chromium (Cr), Manganese (Mn) and Lead (Pb)) and blood hemostatic parameters status after a 3-week exposure cessation among workers exposed to welding fumes. METHODOLOGY: Structured interviews and biological samplings were conducted for 86 male workers without a history of Anemia and Cardiovascular diseases (CVDs) and working in a confined space to construct crude oil tanks. Metal levels of Cr, Mn and Pb in urine were measured during the working days using Inductively Coupled Plasma Mass Spectrometer (ICP-MS) method. The concentrations of hemostatic proteins in blood (White blood cell counts (WBC), Lymphocytes, Monocyte, Eosinophil, Neutrophil, Hematocrit (Hct) were assessed after a 3 weeks exposure cessation. Workers were divided into groups based on occupation type (welder group and non-welder group), and based on metal levels (high and low exposure groups) for comparison. Linear regression models were used to explore the association between metal exposure and multiple blood hemostatic parameters adjusted for age, Body Mass Index (BMI), and smoking status. RESULTS: Urine Mn and Cr level of the welder group was significantly higher than the non-welder group (Mn: 0.96 VS 0.22 ug/g creatinine, p < 0.001; Cr: 0.63 VS 0.22 ug/g creatinine, p < 0.01). The mean value of Hct in the welder group was 44.58 ± 2.84 vol%, significantly higher than the non-welder group (43.07 ± 3.31 vol%, p = 0.026). The median value of WBC in the high Mn-exposed group (6.93 ± 1.59 X 106 Cell/ml) was significantly lower than the low Mn-exposed group (7.90 ± 2.13 X 106 Cell/ml, p = 0.018). The linear regression analyses showed that there was a significantly negative association between log transformed WBC value and the Mn exposure groups (high and low) after adjusting for age, BMI, and smoking status (ß = - 0.049, p = 0.045), but no significant result was found between WBC and occupation types (welder and non-welder) (p > 0.05). Multiple linear regression analysis also showed positive association between Hct and occupational types (welder and non-welders) (ß = 0.014, p = 0.055). The other hemostatic parameters were not different from controls when divided by occupation type or metal level groups. CONCLUSIONS: Our results showed that welders were exposed to about 3 to 4 times higher Mn and Cr concentrations than non-welders. Moreover, one third of the non-welders were exposed to high-exposure groups of Mn and Cr metals. Regression models revealed a significant association of the WBC counts with the Mn exposure group. Therefore, we infer that Mn exposure may play a significant role on the blood hemostatic parameters of workers in the confined space. Hazard identification for non-welders should also be conducted in the confined space.

Assessment of 12 Metals and Metalloids in Blood of General Populations Living in Wuhan of China by ICP-MS.

Assessment of trace element levels in general population from the specific area is of importance for nutritional and occupational monitoring. In the current study, baseline blood levels of 12 toxic and/or essential metals and metalloids, including arsenic (As), cadmium (Cd), lead (Pb), mercury (Hg), chromium (Cr), thallium (Tl), manganese (Mn), copper (Cu), Zinc (Zn), calcium (Ca), iron (Fe), and magnesium (Mg), in general populations (n = 477) of Wuhan in central China were investigated by using inductively coupled plasma mass spectrometry (ICP-MS). The geometric means for As, Cd, Pb, Hg, Cr, Tl, Mn, and Cu were measured as 2.25, 0.70, 17.84, 1.90, 0.36, < 0.05, 12.40, and 783.76 µg/L, respectively. The geometric means for Zn, Ca, Fe, and Mg were 5.85, 56.66, 488.98, and 39.44 mg/L, respectively. We found the men had higher blood As, Pb, Hg, Zn, Fe, and Mg levels but had lower blood Cu and Ca levels than the women (p < 0.05). Age-related difference were found for blood Cu, Zn, Ca, Mg, Pb, Mn, As, Cd, and Hg levels (p < 0.05). Moreover, many metal concentrations were found correlated, with the strongest correlations between the pairs Fe-Mg (r = 0.57), Fe-Zn (r = 0.42), As-Hg (r = 0.46), Ca-Cu (r = 0.34), Pb-Hg (r = 0.36), Pb-Cd (r = 0.31), Pb-As (r = 0.25), and Ca-Fe (r = - 0.23). Compared with reports from other countries, most of our results were consistent, except that As Pb, Hg, Mn, and Cu showed different blood levels with European, Korea, or Beijing areas. Our study would be of importance for nutritional, environmental, and/or occupational monitoring of these metals in human.

Exposure assessment of particulate matter and blood chromium levels in people living near a cement plant.

This study evaluates the effect of air pollution caused by cement plants on nearby residential areas and performs an exposure assessment of particulate matter (PM) and total Cr, Cr6+, Pb, and Al. Further, the blood Cr levels of residents exposed to PM released by cement plants are also assessed. Nine buildings (eight residential and one elementary school building) close to cement plants were selected for this study, which were located in Pyeongtaek port, in west of Gyeonggi Province, South Korea. A total of 51 suspended particulate samples were collected at a flow rate of 2.0 L/min. Total Cr was more widely detected in residents' houses and elementary schools. PM levels were higher at distances of 4.1 and 4.8 km than those at closer distances of 2.7 km. This was due to the influence of wind direction. The estimated mean blood level of Cr for the study participants was 3.80 µg/L, which is higher than levels estimated by other studies on Cr blood levels. Therefore, cement plants could cause an increase in total Cr and blood Cr levels in residential areas, and more continuous monitoring is necessary to better understand their impacts.

Incidence of Adverse Reactions to Metal Debris From 28-mm Metal-on-Metal Total Hip Arthroplasties With Minimum 10 Years of Follow-Up: Clinical, Laboratory, and Ultrasound Assessment of 44 Cases.

BACKGROUND: Total hip arthroplasty with metal-on-metal (MoM) bearings has been suspected to cause adverse reactions to metal debris (ARMD), with the incidence varying greatly by implant type and patient gender. The prevalence of ARMD from small-diameter MoM bearings in women is unknown, especially after 10 years of follow-up (FU). METHODS: Cementless 28-mm MoM total hip arthroplasty bearings (Metasul) were implanted consecutively in 42 active women between 1996 and 2002. They were reviewed after a minimum of 10 years' FU with clinical, laboratory, radiological, and ultrasound assessments. RESULTS: Mean FU was 15.9 years (range, 13-18). The mean Postel-Merle d'Aubigné and Oxford scores were 16.9 (range, 13-18) and 15.1 (range, 12-24), respectively, at FU. Mean cup inclination angle was 46.3° (range, 35°-57°). No femoral osteolysis was detected, but limited acetabular osteolysis (11%) over the screw holes occurred in 5 cases. No liquid or solid synovial reactions or ARMD were apparent on ultrasound, even in the 5 cases of pelvic osteolysis. Mean chromium levels were 1.32 µg/L (range, 0.1-7.9) and cobalt levels were 1.85 µg/L (range, 0.35-13.6). Cobalt was >3 µg/L in only 3 cases. The 15.9-year survivorship was 95% (range, 94.1%-98.9%). CONCLUSION: Reliable results were obtained with 28-mm MoM bearings, notably in young, active patients. This implant configuration requires very accurate positioning. No ARMD was seen in this group at 16 years' FU.

[Morbidity and content of microelements in the blood of school children residing near chromium enterprises].

For the first time there was investigated the content of certain microelements in the blood of children of school age residing in the city of Aktobe (Kazakhstan), where the global giants, mining andprocessing chrome ore productions are located. There were determined blood levels of chromium, nickel, lead in children. There was shown the difference in the blood content of microelements in children, depending on region of residence and their correlation with the core indices of health and disease.

Metal-on-metal hip resurfacing: correlation between clinical and radiological assessment, metal ions and ultrasound findings.

PURPOSE: We report the clinical, radiological and wear analysis of 52 consecutive MoM hip resurfacings (performed on 49 younger patients) to a mean follow-up of 9.2 years. METHODS: Every patient underwent X-ray and clinical evaluation (HHS). Ultrasonography of the hip was performed in all patients in order to identify possible cystic or solid mass in periprosthetic tissue. In case of mass >20 mm, further MRI was performed to better analyse the characteristics of lesion. RESULTS: Five patients (five hips) had a revision. The overall survival rate was 90.38 %. The average HHS at follow-up examination was 95.5 points. No progressive radiolucent areas and no sclerosis or osteolysis around the implants were found. The US and RMI imaging showed a pseudotumour formation in two patients (correlated with high metal ion levels in blood and urine), both asymptomatic. CONCLUSION: A significant positive correlation between inclination of the acetabular component and serum metal ion levels was found (r = 0.64 and r = 0.62 for cobalt and chromium, respectively).

Chemometrics models for assessment of oxidative stress risk in chrome-electroplating workers.

Oxidative stress is the main cause of hexavalant chromium-induced damage in chrome electroplating workers. The main goal of this study is toxicity analysis and the possibility of toxicity risk categorizing in the chrome electroplating workers based on oxidative stress parameters as prognostic variables. We assessed blood chromium levels and biomarkers of oxidative stress such as lipid peroxidation, thiol (SH) groups and antioxidant capacity of plasma. Data were subjected to principle component analysis (PCA) and artificial neuronal network (ANN) to obtain oxidative stress pattern for chrome electroplating workers. Blood chromium levels increased from 4.42 ppb to 10.6 ppb. Induction of oxidative stress was observed by increased in lipid peroxidation (22.38 ± 10.47 µM versus 14.74 ± 4.82 µM, p < 0.0008), decreased plasma antioxidant capacity (3.17 ± 1.35 µM versus 7.74 ± 4.45 µM, p < 0.0001) and plasma total thiol (SH groups) (0.21 ± 0.07 µM versus 0.45 ± 0.41 µM, p < 0.0042) in comparison to controls. Based on the oxidative parameters, two groups were identified by PCA methods. One category is workers with the risk of oxidative stress and second group is subjects with probable risk of oxidative stress induction. ANN methods can predict oxidative-risk category for assessment of toxicity induction in chrome electroplaters. The result showed multivariate modeling can be interpreted as the induced biochemical toxicity in the workers exposed to hexavalent chromium. Different occupation groups were assessed on the basis of risk level of oxidative stress which could further justify proceeding engineering control measures.

Assessment of health risks with reference to oxidative stress and DNA damage in chromium exposed population.

Trivalent chromium [Cr(III)] is widely used in tanning industrial processes. The population living in tanning industrial area is continuously exposed to Cr(III) which appears to be associated with both acute and chronic health problems. Therefore, the aim of this study was to evaluate the health risk with special reference to oxidative stress parameters (malondialdehyde - MDA, glutathione - GSH, and superoxide dismutase - SOD) and DNA damage in 100 Cr-exposed and 100 unexposed populations. The total blood Cr level, SOD level, MDA level and DNA damage were significantly (p<0.05) higher and GSH level was significantly (p<0.05) lower in exposed group as compared to the unexposed group. The altered oxidative stress parameters and DNA damage were found to be slightly higher in female population of both groups. In simple and multiple correlation analyses (adjusted with potential confounders), blood Cr level showed negative significant correlation with GSH level and positive significant correlation with level of MDA, SOD and DNA damage in both groups. The overall prevalence of morbidity was found to be significantly (p<0.05) higher in the exposed group as compared to the unexposed group. In the exposed group, the prevalence of respiratory illness is highest, followed by diabetes, gastrointestinal tract problems and dermal problems respectively. Our results concluded that the Cr(III) exposed population is at high risk for health hazards and the female population is slightly more susceptible to Cr(III) exposure.

[Assessment of the level of metal ions in the blood of patients after hip resurfacing--preliminary report]. / Ocena poziomu jonów metali we krwi pacjentów po endoprotezoplastyce powierzchniowej--doniesienie wstepne.

INTRODUCTION: Metal-on-metal bearings characterize lower wear than metal-poly, lower fracture risk than ceramics and they allow for the manufacturing of large diameter heads. The metal ion release from the bearings is the the major concern of these articulations. MATERIAL: The study group consisted of 16 patients who underwent hip resurfacing with Durom implant and had minimum 1 year follow-up period. Blood from the patients was collected 4 times: before the surgery, 2, 6 and 12 months postoperatively. METHODS: Clinical examination was done according to HHS, Radiographic image was used to measure the cup inclination, evaluation of chromium and cobalt ion blood levels was performed using graphite furnace atomic absorbtion spectrometry (GFAAS). RESULTS: The levels of cobalt and chromium increased postoperatively significantly to decrease slightly at 6 months. At 1 year cobalt levels increased to the similar level like at at 2 months. The chromium level decresed to the values as low as preoperatively. The mean cup inclination angle measured on X-rays was 48 degrees(range 39 degrees - 56 degrees). The mean HHS result was 89.86 (range 64.43 to 98.73). The mean activity level measured with UCLA scale was 6 (range 3-9). CONCLUSIONS: The metal ion blond levels increase sigficantly in the period 2-6 months following hip replacement with large diameter metal-on-metal articulation. In further examinations at 1 year post-op ion levels decrease.

Biomonitoring on carcinogenic metals and oxidative DNA damage in a cross-sectional study.

Oxidative DNA damage is mediated by reactive oxygen species and is supposed to play an important role in various diseases including cancer. The endogenous amount of reactive oxygen species may be enhanced by the exposure to genotoxic metals. A cross-sectional study was conducted from 1993 to 1994 in an urban population in Germany to investigate the association between metal exposure and oxidative DNA damage. The cross-sectional sample of 824 participants was recruited from the registry of residents in Bremen, comprising about two-third males and one-third females with an average age of 61.1 years. A standardized questionnaire was used to obtain the occupational and smoking history. The incorporated dose of exposure to metals was assessed by biological monitoring. Chromium, cadmium, and nickel were measured in 593 urine samples. Lead was determined in blood samples of 227 participants. As a biomarker for oxidative DNA damage, 7,8-dihydro-8-oxoguanine has been analyzed in lymphocytes of 201 participants. Oxidative lesions were identified by single strand breaks induced by the bacterial formamidopyrimidine-DNA glycosylase (Fpg) in combination with the alkaline unwinding approach. The concentrations of metals indicate a low body load (median values: 1.0 microg nickel/l urine, 0.4 microg cadmium/l urine, and 46 microg lead/l blood; 83% of chromium measures were below the technical detection limit of 0.3 microg/l). The median level of Fpg-sensitive DNA lesions was 0.23 lesions/10(6) bp. A positive association between nickel and the rate of oxidative DNA lesions (Fpg-sensitive sites) was observed (odds ratio, 2.15; tertiles 1 versus 3, P < 0.05), which provides further evidence for the genotoxic effect of nickel in the general population.

Danish external quality assessment scheme: an interlaboratory comparison study on lead, cadmium and chromium in lyophilized human blood concentrate.

A Danish External Quality Assessment Scheme (EQAS) was carried out by the Danish National Institute of Occupational Health during the period 1988-1992. The scheme was implemented for 29 international laboratories from 15 countries assaying lead, cadmium, and chromium in human blood to ascertain the systematic error and uncertainty of the analytical methods. In the survey the quality control material AMI B701-B705, based on lyophilized human whole-blood concentrate, were used. As an estimate of the true values the reference values used in this evaluation were (a) the computed values, i.e., sum of the basal and spiked trace element concentration, and (b) the consensus values normally used in the Danish EQAS. This international evaluation of lead, cadmium, and chromium in human blood demonstrated that the use of lyophilized human blood concentrate quality control materials combined with this scheme is valuable in estimating the systematic error and the uncertainty of the analytical methods. For evaluating analytical performance, the computed values were preferable to the consensus values for lead and cadmium in human blood. Due to analytical difficulties suitable reference values were not established for chromium in blood. The study revealed analytical difficulties for cadmium and chromium in human blood. The assessment of laboratories according to established performance indexes indicates that few laboratories can maintain these performance indexes.

Chromium exposure assessment of outdoor workers in Hudson County, NJ.

A large quantity of chromate chemical production waste, containing hexavalent chromium, has been used as fill at over 150 sites in Hudson County, New Jersey. One site is in a state park, and several other sites are adjacent to the park. Blood and urinary chromium levels were compared between 17 employees at the Hudson County park and 35 employees from two other state parks. A limited number of soil and personal air samples were also taken. Urinary and RBC chromium levels between the two groups were similar, even after adjusting for potentially confounding variables. The air sampling results demonstrated slightly higher chromium levels at Hudson County, but these were still very low level in nature (mean = 0.18 micrograms/m3). These results call into question the utility of chromium biomonitoring under environmental exposure conditions.

Biological markers in chromium exposure assessment: confounding variables.

An estimated two million tons of chromate production waste pollution has caused a major environmental and public health concern in Hudson County, New Jersey. As part of an occupational exposure assessment, urinary and red blood cell (RBC) chromium measurements were performed on 52 state employees who worked either near a contaminated site or elsewhere. Samples were collected so as to minimize contamination, and they were analyzed using sensitive techniques. These workers also completed a questionnaire that addressed potentially important third variables. Individual analyses suggested that exercise, drinking beer, past employment in chromium-related occupations, and diabetic status had an important effect on urinary chromium levels. These variables were entered into a regression model and were all found to be significant predictors of urinary chromium level (p less than .10). Some variables were also examined for their influence on RBC chromium level, but none had a measurable effect.

Use of the artificial beta cell (ABC) in the assessment of peripheral insulin sensitivity: effect of chromium supplementation in diabetic patients.

The artificial beta cell (ABC), a closed-loop insulin delivery system, was used to determine insulin sensitivity. Progressively increasing glucose loads were administered after initial stabilization of the blood glucose at euglycemic levels such that the serum C-peptide was suppressed. The amount of insulin required to maintain euglycemia was considered a measure of sensitivity to insulin. Six stable maturity onset diabetics were studied before and after supplementation with chromium-rich brewer's yeast. All patients demonstrated an increase in sensitivity to insulin as indicated by a decrease in the fasting blood glucose concentration and a decrease in insulin requirement during the glucose challenge (P less than 0.02). The data obtained support the hypothesis that chromium or some other factor(s) present in brewer's yeast potentiates the peripheral effects of insulin. It remains to be established whether this effect occurs at the receptor or post-receptor level.