Trend in blood lead levels in Taiwanese adults 2005-2017

A ZnO-nanorod/PEDOT:PSS nanocomposite functionalized bridge-like membrane type nanomechanical sensing device for ultrasensitive blood lead detection

Lead (Pb) ion detection poses a critical problem, particularly in environmental monitoring, industrial operations, and public health, especially for young children and expecting women. Determining lead levels in blood early on is essential to minimizing the long-term consequences of lead exposure. Several sophisticated detection instruments, such as mass spectrometers which perform with high sensitivity, specificity and accuracy, but require a lab-based setting, multi-step sample preparation, expensive payment and professional operation. It is evident that a highly sensitive, portable, low-cost, quick sample-to-result, blood lead detection device that can be tested at the point-of-care is necessary. Consequently, we developed a unique ZnO/PEDOT:PSS nanocomposite layer integrated with a CMOS MEMS-based bridge-like membrane-type (BM) nanomechanical sensor for detecting lead levels in blood. PEDOT:PSS was combined with ZnO nanorods to increase lead ion binding. The sensor responds seven times better to lead ions using nanorods in the detecting layer. A linear resistance change rate response was found from 0.005 to 10 ppm, with the limit of detection (LOD) of 0.12 ppb. Similarly, our BM nanomechanical sensor can correctly assess Pb2+ in human serum with recovery rates of 86.25-150 %. Measurements of human blood samples from patients with varying lead ion concentrations validated by the standard AAS show a good linear connection with the BM nanomechanical sensors' concentration, with a regression coefficient of 0.92. This describes the first micromachined nanoachanical sensing system for detection of Pb2+ in only 5 μL of human serum sample. The device achieves a time-to-result of less than 10 min. The system is designed to be very sensitive and offers affordable, disposable sensing chips together with a portable signal acquisition platform.

Blood lead (Pb) is associated with lung fibrotic changes in non-smokers living in the vicinity of petrochemical complex: a population-based study

Lead (Pb) is a toxic metal that has been extensively used in various industrial processes, and it persists in the environment, posing a continuous risk of exposure to humans. This study investigated blood lead levels in participants aged 20 years and older, who resided in Dalinpu for more than two years between 2016 to 2018, at Kaohsiung Municipal Siaogang Hospital. Graphite furnace atomic absorption spectrometry was used to analyze the blood samples for lead levels, and the LDCT (Low-Dose computed tomography) scans were interpreted by experienced radiologists. The blood lead levels were divided into quartiles, with Q1 representing levels of ≤1.10 μg/dL, Q2 representing levels of >1.11 and ≤1.60 μg/dL, Q3 representing levels of >1.61 and ≤2.30 μg/dL, and Q4 representing levels of >2.31 μg/dL. Individuals with lung fibrotic changes had significantly higher (mean ± SD) blood lead levels (1.88±1.27vs. 1.72±1.53 μg/dl, p< 0.001) than those with non-lung fibrotic changes. In multivariate analysis, we found that the highest quartile (Q4: >2.31 μg/dL) lead levels (OR: 1.36, 95% CI: 1.01-1.82; p= 0.043) and the higher quartile (Q3: >1.61 and ≤2.30 μg/dL) (OR: 1.33, 95% CI: 1.01-1.75; p= 0.041) was significantly associated with lung fibrotic changes compared with the lowest quartile (Q1: ≤1.10 μg/dL) (Cox and Snell R², 6.1 %; Nagelkerke R², 8.5 %). The dose-response trend was significant (P_trend= 0.030). Blood lead exposure was significantly associated lung fibrotic change. To prevent lung toxicity, it is recommended to maintain blood lead levels lower than the current reference value.

Immune Responses to COVID-19 Vaccines in Patients with Chronic Kidney Disease and Lead Exposure

Literature data regarding the response rate to COVID-19 vaccination in chronic kidney disease (CKD) patients remain inconclusive. Furthermore, studies have reported a relationship between lead exposure and susceptibility to viral infections. This study examined immune responses to COVID-19 vaccines in patients with CKD and lead exposure. Between October and December 2021, 50 lead-exposed CKD patients received two doses of vaccination against COVID-19 at Chang Gung Memorial Hospital. Patients were stratified into two groups based on the median blood lead level (BLL): upper (≥1.30 μg/dL, n = 24) and lower (<1.30 μg/dL, n = 26) 50th percentile. The patients were aged 65.9 ± 11.8 years. CKD stages 1, 2, 3, 4 and 5 accounted for 26.0%, 20.0%, 22.0%, 8.0% and 24.0% of the patients, respectively. Patients in the lower 50th percentile of BLL had a lower proportion of CKD stage 5 than patients in the upper 50th percentile BLL group (p = 0.047). The patients in the lower 50th percentile BLL group also received a higher proportion of messenger RNA vaccines and a lower proportion of adenovirus-vectored vaccines than the patients in the upper 50th percentile BLL group (p = 0.031). Notably, the neutralizing antibody titers were higher in the lower 50th percentile than in the upper 50th percentile BLL group. Furthermore, the circulating levels of granulocyte-colony stimulating factor, interleukin-8, monocyte chemoattractant protein-1 and macrophage inflammatory protein-1α were higher in the upper 50th percentile than in the lower 50th percentile BLL group. Therefore, it was concluded that lead-exposed CKD patients are characterized by an impaired immune response to COVID-19 vaccination with diminished neutralizing antibodies and augmented inflammatory reactions.