Factors Influence on Pap Test Screening among Lahu Hill Tribe Women in Remote Area Thailand.

BACKGROUND: Papanicolaou test is widely used to screening cervical cancer but low attend rate. There is one mountainous area found high participation rate. OBJECTIVE: This study aimed to determine the factors associated with successful Pap test among Lahu hill tribe women. MATERIALS AND METHODS: The quantitative cross-sectional study was used in this study. Data were collected from 650 Lahu hill tribe women by simple random sampling. The interview forms with reliability coefficient and validity of 0.78 and 0.91 were administered to participants. The data were analyzed by using descriptive statistics and Chi-square test. RESULTS: The 96.15% of the Lahu hill tribe women had taken Pap test and 74.31% obtained the screening more than once. The contraceptive use and frequency of Pap test obtaining significantly associated with cervical cancer screening (p <0.001). The participants showed good level of knowledge in cervical cancer and the screening test (64.31% and 76.46% respectively). Most of participants received the cervical cancer disease information (87.17%) and screening information (66.92%) from health care professionals, which may influence on well cervical screening co-operation.  Conclusions: The suitable health promotion model should provide to promote knowledge, attitude and motivate continuous cooperation in cervical cancer screening among hill tribe women.

Pesticide exposure and adverse health effects associated with farmwork in Northern Thailand.

OBJECTIVES: To assess pesticide exposure and understand the resultant health effects of agricultural workers in Northern Thailand. METHODS: This was a cross-sectional study. We quantified exposure to pesticides, including chlorpyrifos, methomyl, and metalaxyl, by air sampling and liquid chromatography/mass spectrometry. We estimated differences in self-reported health outcomes, complete blood counts, cholinesterase activity, and serum/urine calcium and creatinine concentrations at baseline between farmworkers and comparison workers, and after pesticide spraying in farmworkers only. RESULTS: This study included 97 men between the ages of 22 and 76 years; 70 were conventional farmworkers; and 27 did not report any prior farmwork or pesticide spraying. None of the farmworkers wore standardized personal protective equipment (PPE) for the concentrated chemicals they were working with. Methomyl (8.4-13 481.9 ng/m3 ), ethyl chlorpyrifos (11.6-67 759 ng/m3 ), and metalaxyl (13.9-41 191.3 ng/m3 ) were detected via personal air sampling. When it came to reporting confidence in the ability to handle personal problems, only 43% of farmworkers reported feeling confident, which reflects higher stress levels in comparison to 78% of comparison workers (P = .028). Farmworkers also had significantly lower monocyte counts (P = .01), serum calcium (P = .01), red blood count (P = .01), white blood cell count (P = .04), and butyrylcholinesterase activity (P < .0001), relative to comparison workers. After adjusting for body mass index (BMI), age, and smoking, methomyl air concentrations were associated with a decrease in farmworker acetylcholinesterase activity (beta = -0.327, P = .016). CONCLUSIONS: This population of farmworkers had significant alterations in stress measures and clinical biomarkers, including decreased blood cell counts and cholinesterase activity, relative to matched controls. These changes are potentially linked to occupational pesticide exposures. Improving PPE use presents a likely route for preventive intervention in this population.

Metal Levels, Genetic Instability, and Renal Markers in Electronic Waste Workers in Thailand.

BACKGROUND: Informal electronic waste (e-waste) recycling is an increasingly important industry worldwide. However, few studies have studied the health risks in this group of workers. OBJECTIVE: To assess the associations between occupational exposures to metals and genetic instability and renal markers among e-waste recycling workers. METHODS: We recruited informal e-waste recycling workers from a community in northeastern Thailand. Participants completed a questionnaire, several health measurements, and provided urine and blood samples, which we then analyzed for a number of metals including lead (Pb), cadmium (Cd), and manganese (Mn). Samples were analyzed for a marker of RNA and DNA damage (ie, oxidative stress), 8-hydroxy-2'-deoxyguanosine (8-OHdG). Glomerular filtration rate (GFR) and fractional excretion of calcium (FECa%) were measured as markers of renal function. Correlations and regression models were used to assess associations between these various factors. RESULTS: We found significantly higher levels of Cd and Pb in blood of men compared with those in women. Men who worked >48 hours/week had significantly higher levels of 8-OHdG compared with men who worked ≤48 hours/week. Smoking was significantly associated with higher blood Pb and Cd concentrations among men. CONCLUSION: Our results suggest gender differences in both blood concentrations of metals associated with e-waste recycling and smoking and highlight potentially elevated oxidative stress associated with longer work hours. Health promotion efforts are needed among informal e-waste recyclers to reduce possible risks of renal damage and cancer.

Bone Fracture Risk and Renal Dysfunction in a Highly Cadmium Exposed Thai Population.

BACKGROUND: Paddy fields in the Mae Sot, Tak Province of Thailand are polluted with unsafe levels of cadmium (Cd). Elderly populations have a high Cd body burden, putting them at elevated risk of renal dysfunction and bone fractures. We aimed to compare bone fracture risk between glomerular dysfunction, proximal tubular dysfunction, and calcium (Ca) handling abnormalities. STUDY DESIGN: A cross-sectional study. METHODS: Serum osteocalcin and cross-linked N-telopeptide of type I collagen were used to detect bone metabolism abnormalities, whereas glomerular filtration rate, serum cystatin C, urinary ß2-microglobulin (ß2-MG) and fractional excretion of calcium (FECa) were used to indicate renal dysfunction. Urinary Cd was used as an exposure marker. RESULTS: FECa >2% was associated with high bone fracture risk in both genders. The adjusted odds of bone fracture risk were 6.029 and 3.288 in men and women, respectively with FECa >2% relative to the FECa < 2% group. Proximal tubular dysfunction and glomerular dysfunction did not significantly relate to the risk of bone fracture. CONCLUSIONS: Abnormal Ca handling is a key risk factor for bone fracture in Cd-exposed people. Men and women were at risk of bone fracture risk at a similar rate. FECa was a specific indicator of Ca wasting and was more cost-effective compared to ß2-MG and serum cystatin C. We recommend using FECa to monitor abnormal Ca metabolism in individuals with FECa>2%. Reduced renal toxicant exposure and Ca supplementation are recommended for Cd-exposed populations to reduce bone fracture risk.

Cadmium Exposure Inhibits Branching Morphogenesis and Causes Alterations Consistent With HIF-1α Inhibition in Human Primary Breast Organoids.

Developmental cadmium exposure in vivo disrupts mammary gland differentiation, while exposure of breast cell lines to cadmium causes invasion consistent with the epithelial-mesenchymal transition (EMT). The effects of cadmium on normal human breast stem cells have not been measured. Here, we quantified the effects of cadmium exposure on reduction mammoplasty patient-derived breast stem cell proliferation and differentiation. Using the mammosphere assay and organoid formation in 3D hydrogels, we tested 2 physiologically relevant doses of cadmium, 0.25 and 2.5 µM, and tested for molecular alterations using RNA-seq. We functionally validated our RNA-seq findings with a hypoxia-inducible factor (HIF)-1α activity reporter line and pharmaceutical inhibition of HIF-1α in organoid formation assays. 2.5 µM cadmium reduced primary mammosphere formation and branching structure organoid formation rates by 33% and 87%, respectively. Despite no changes in mammosphere formation, 0.25 µM cadmium inhibited branching organoid formation in hydrogels by 73%. RNA-seq revealed cadmium downregulated genes associated with extracellular matrix formation and EMT, while upregulating genes associated with metal response including metallothioneins and zinc transporters. In the RNA-seq data, cadmium downregulated HIF-1α target genes including LOXL2, ZEB1, and VIM. Cadmium significantly inhibited HIF-1α activity in a luciferase assay, and the HIF-1α inhibitor acriflavine ablated mammosphere and organoid formation. These findings show that cadmium, at doses relevant to human exposure, inhibited human mammary stem cell proliferation and differentiation, potentially through disruption of HIF-1α activity.

Gender-Specific Impact of Cadmium Exposure on Bone Metabolism in Older People Living in a Cadmium-Polluted Area in Thailand.

To elucidate the influence of cadmium exposure on bone metabolism, associations between urinary/blood cadmium and bone resorption/formation markers were investigated in older cadmium exposed men and women. Increased urinary cross-linked N-telopeptide of type I collagen (NTx), a bone resorption marker, was found to be associated with increased levels of parathyroid hormone, fractional excretion of calcium, and urinary/blood cadmium after adjusting for confounding factors in men. In women, urinary NTx was significantly associated with only urinary cadmium and a strong relationship with increased fractional excretion of calcium. Risk for bone metabolic disorders, indicated by high urinary NTx, significantly increased in men with blood cadmium ≥ 10 µg/L or urinary cadmium ≥ 10 µg/g creatinine. Increased osteocalcin level was significantly associated with increased blood cadmium in men. In conclusion, cadmium exposure appeared to have an influence on bone remodeling both bone resorption and formation in this population of older Thai men, and blood cadmium was more closely associated with bone metabolism than urinary cadmium.

Cadmium exposure and age-associated DNA methylation changes in non-smoking women from northern Thailand.

DNA methylation changes with age, and may serve as a biomarker of aging. Cadmium (Cd) modifies cellular processes that promote aging and disrupts methylation globally. Whether Cd modifies aging processes by influencing establishment of age-associated methylation marks is currently unknown. In this pilot study, we characterized methylation profiles in > 450 000 CpG sites in 40 non-smoking women (age 40-80) differentially exposed to environmental Cd from Thailand. Based on specific gravity adjusted urinary Cd, we classified them as high (HE) and low (LE) exposed and age-matched within 5 years. Urinary Cd was defined as below 2 µg/l in the LE group. We predicted epigenetic age (DNAm-age) using two published methods by Horvath and Hannum and examined the difference between epigenetic age and chronologic age (Δage). We assessed differences by Cd exposure using linear mixed models adjusted for estimated white blood cell proportions, BMI, and urinary creatinine. We identified 213 age-associated CpG sites in our population (P < 10-4). Counterintuitively, the mean Δage was smaller in HE vs. LE (Hannum: 3.6 vs. 7.6 years, P = 0.0093; Horvath: 2.4 vs. 4.5 years, P = 0.1308). The Cd exposed group was associated with changes in methylation (P < 0.05) at 12, 8, and 20 age-associated sites identified in our population, Hannum, and Horvath. From the results of this pilot study, elevated Cd exposure is associated with methylation changes at age-associated sites and smaller differences between DNAm-age and chronologic age, in contrast to expected age-accelerating effects. Cd may modify epigenetic aging, and biomarkers of aging warrant further investigation when examining Cd and its relationship with chronic disease and mortality.

Risk assessment for Thai population: benchmark dose of urinary and blood cadmium levels for renal effects by hybrid approach of inhabitants living in polluted and non-polluted areas in Thailand.

BACKGROUND: The aim of the present study was to estimate the benchmark doses (BMD) for renal effects for health risk assessment of residents living in Cd-polluted and non-polluted areas in a Thai population. METHODS: The study participants consisted of inhabitants aged 40 years or older who lived in a non-polluted area (40 men and 41 women) and in the environmentally polluted Mae Sot District (230 men and 370 women) located in northwestern Thailand. We measured urinary and blood cadmium (Cd) as markers of long-term exposure and urinary ß2-microglobulin (ß2-MG) and N-acetyl-ß-D-glucosaminidase (NAG) as renal tubular effect markers. An updated hybrid approach was applied to estimate the benchmark doses (BMD) and their 95% lower confidence limits (BMDL) of urinary and blood Cd for Cd-induced renal effects in these subjects. BMD and BMDL corresponding to an additional risk (BMR) of 5% were calculated with the background risk at zero exposure set to 5% after adjusting for age and smoking status. RESULTS: The estimated BMDLs of urinary Cd for renal effect markers were 6.9 for urinary ß2-MG and 4.4 for NAG in men and 8.1 for ß2-MG and 6.1 for NAG µg/g creatinine (Creat) in women. These BMDLs of urinary Cd (µg/g Creat) for NAG were less than the geometric mean urinary Cd in the polluted area (6.5 in men and 7.1 in women). The estimated BMDLs of blood Cd (µg/L) were 6.2 for urinary ß2-MG and 5.0 for NAG in men and 5.9 for ß2-MG and 5.8 for NAG in women. The calculated BMDLs were similar or less compared with the geometric mean blood Cd (µg/L) in the polluted Thai area (6.9 in men and 5.2 in women). CONCLUSION: The BMDLs of urinary and blood Cd for renal effects were estimated to be 4.4-8.1 µg/g Creat and 4.4-6.2 µg/L in the Thai population aged ≥ 40 years old, suggesting that more than 40% of the residents were at risk of adverse renal effects induced by Cd exposure in Thailand.

Use of the kidney injury molecule-1 as a biomarker for early detection of renal tubular dysfunction in a population chronically exposed to cadmium in the environment.

Cadmium (Cd) has been found as an environmental pollutant in Mae Sot district, Tak province, Thailand. Prolong exposure to high levels of Cd of the resident increases high risk of Cd toxicity especially to kidney which is the primary target of Cd. In order to investigate the early effect of Cd induced renal dysfunction, a kidney injury molecule-1 (KIM-1), a novel biomarker of renal tubular dysfunction, was measured using an enzyme linked immunosorbent assay (ELISA). The method was validated and used to quantify the KIM-1 concentrations in the urine of 700 subjects (260 men, 440 women) who lived in the Cd contaminated area. The KIM-1 concentrations were compared to the concentrations of two conventional renal tubular dysfunction biomarkers, N-acetyl-ß-D-glucosaminidase (NAG) and ß2-microglobulin (ß2-MG). Urinary KIM-1 was correlated with urinary and blood Cd as well as NAG. After adjustment of age and smoking, urinary KIM-1 was correlated with blood Cd more than urinary NAG did. Clear dose response relationships of urinary KIM-1 with urinary Cd were shown in both men and women. These results indicate that the urinary KIM-1 might be more sensitive biomarker than urinary NAG and ß2-MG for an early detection of renal tubular dysfunction. It is useful as a tool to detect renal effect of toxicity due to chronic Cd exposure at high level.

Cadmium-exposed population in Mae Sot District, Tak Province: 4 bone mineral density in persons with high cadmium exposure.

OBJECTIVE: To measure bone mineral density in cadmium-exposed persons aged 40 years and older that lived in the 12 contaminated villages in northwestern Thailand. MATERIAL AND METHOD: Five hundred seventy three persons with urinary cadmium levels > or = 5 microg/g creatinine during the 2004-2006 surveys were screened in 2007 for urinary excretion of cadmium, bone formation and resorption markers, and renalfunction markers. Calcaneus bone density was measured in each person by a dual-energy X-ray absorptiometry bone scanner. RESULTS: The mean age of the study persons was 57 years old. The geometric mean level of urinary cadmium for women was significantly higher than that for men. Women had a lower mean of calcaneus bone density than men. The rate of osteoporosis in women (21.5%) was significantly higher than that for men (14.7%). Calcaneus bone density was negatively correlated with urinary excretion of calcium (in both genders) and crosslinked N-telopeptide of type I collagen (in women), after adjusting for other co-variables. Increasing urinary cadmium levels appeared to correlate with reduced bone density in women, but not in men. In both genders, urinary excretion of beta2-microglobulin and N-acetyl-beta-D-glucosaminidase was higher in persons with osteoporosis than those without. CONCLUSION: Bone mineral loss is correlated with urinary cadmium levels and renal dysfunction in this female population.

Bone resorption acceleration and calcium reabsorption impairment in a Thai population with high cadmium exposure.

Some residents of the Mae Sot district in Thailand have suffered long-term exposure to elevated dietary levels of cadmium. To test the hypothesis that chronic dietary cadmium exposure can cause imbalance in calcium dynamics and accelerate bone resorption, a group of these residents (156 men and 256 women aged >/= 50) were selected on the basis of previous records of elevated urinary cadmium and tested for urinary and blood cadmium, bone formation and resorption markers, and the renal tubular dysfunction markers. Both genders had high levels of blood and urinary cadmium and high urinary levels of the markers for renal dysfunction and bone resorption in a dose-response relationship to urinary cadmium. The excretion of bone resorption markers was positively correlated to the ratio of excreted calcium and urinary cadmium. The results of a multivariate regression analysis indicated that bone resorption was accelerated by impaired calcium reabsorption in renal tubules.