Page 29 - JCTR-10-3

Gupta et al. | Journal of Clinical and Translational Research 2024; 10(3): 201-208 203
measures were taken. A structured data collection instrument, interview. The laboratory technicians were kept blinded, and all
comprising information about sociodemographic details blood testing reports were shared with the participants.
(e.g., age, smoking status, alcohol ingestion, and duration of The four water sources were evaluated in each group of
occupational exposure) and clinical details, was developed. This participants. The first sample was the first water from the tap
instrument was pretested, suitably modified, and subsequently in any randomly selected participants’ houses within the study
implemented. Basic sociodemographic information (e.g., area. The second water sample was from a 20-L packed plastic
family size, age, education, occupation, gender of members of can of water available in the vicinity of the above house. The
the family, and occupational years) was collected to study the third water sample was from the water purifier in any of the
correlation of these factors to the risk of high BLL. randomly selected participants’ houses. The fourth water sample
In this study, BLL was considered the outcome variable, while was from the tap at the nearest health-care facility, school, or
the exposure variables include the participants’ occupation, age, office from the selected participants’ house.
education, smoking status, and alcohol intake, among others.
2.3. Data analysis
2.2. Blood sample collection
Data were entered in Microsoft Excel and analyzed by using
Blood samples (3 mL) were collected under sterile IBM SPSS Statistics Base version 28.0. Lead exposures at
conditions using BD Vacutainer® Eclipse™ blood collection baseline were categorized into three groups. The continuous
needles (368608; BD, USA) into BD Vacutainer® EDTA variables in the study (i.e., BLLs) were summarized as
tubes (367861; BD, USA) containing EDTA K2 anticoagulant mean ± SD. Normality was assessed using the Kolmogorov–
for BLL measurements. The blood samples were transported Smirnov test. The categorical variables, including age, gender,
to the AIIMS Mangalagiri Biochemistry Laboratory, while and occupational exposure, were presented as frequency or
maintaining a cold chain (i.e., in cold boxes with temperature percentage.
monitors). At the laboratory, the samples were processed Bivariate analysis of categorical parameters, i.e., comparison
accordingly. In a 100 mL volumetric flask, 5 mL of 10% of BLLs, was performed using the Chi-square (χ ) test. The
2
Triton X-100, 2 mL of NH PO , and four drops of 70% HNO mean BLLs of the three groups were compared using analysis of
3
4
4
were mixed and diluted to volume with deionized water to variance with post hoc analysis. Multivariate logistic regression
form the matrix modifier. To prepare a multipoint calibration was performed to distinguish the exposure variables according
curve, 0.1, 5, 10, 30, and 60 µg/dL working standard lead- to BLL < or ≥5 µg/dL. Statistical significance was defined as
containing solutions were prepared in 1% HNO . The final P < 0.05.
3
standard solutions were prepared by mixing 100 µL of each of
the working standard solutions with 900 µL of matrix modifier 3. Results
in autosampler vessels to produce 0.1, 0.5, 1, 3, and 6 µg/dL,
respectively. These standard solutions were set aside until the Approximately 65.56% of participants were less than
bubbles dissipated. The samples were then prepared by mixing 40 years old, with a mean age of 35.65 ± 9.21 years; 74.44% of
100 µL of whole blood (with anticoagulant) with a 900 µL participants were males; 68.33% of participants were are at least
th
matrix modifier. BLLs were estimated using a graphite furnace 10 class (i.e., more educated); 47.22% of participants belonged
atomic absorption spectrophotometer. The trace element blood to the upper middle socioeconomic status (Table 1). The median
collection tubes used here refer to BD Vacutainer® specialty (interquartile range [IQR]) of family and individual incomes
tubes (368381; BD, USA). The BLL measurement method has were INR 20000 (15000) and INR 15000 (8500), respectively.
been validated with an estimated detection limit of <1 µg/dL Table 2 reports that 17.78% of participants were smokers and
and requires only a small sample size. The measurement method 3.8% used smokeless tobacco. Overall, 37.78% of participants
also has a multi-element capacity with little interference. reported that their house was within a 1 km radius of the
Information about the study was shared with the communities highway or traffic zone. Approximately 50.56% of participants
through field health workers, schools, Anganwadi, and social were using 20-L canned water for drinking.
media. Any eligible participants (for either one of the three Table 3 reports that 36.7% of participants were painters and
groups) visiting the AIIMS hospital or the Centre for Rural 30.0% were construction workers in Group 1; 50.0% were traffic
Health AIIMS Nutakki were enrolled using purposively police and 33.3% were auto drivers in Group 2; and 41.7% were
sampling. Furthermore, independent camps were conducted at primary health-care workers (accredited social health activist
peripheral centers. The investigator introduced himself/herself [ASHA] and Anganwadi) and 40.0% were office workers in
to the participant before the start of the interview. Individuals Group 3. The median (IQR) working hours in a typical day
were given patient information sheets. Thereafter, the research was 8 (2) h. The median (IQR) number of years in the present
team explained the study, its objectives, procedure, and the occupation of study participants was 10 (11.7) years.
rights of the participants. If the individuals agreed to participate Figure 1 displays the violin plot of the distribution of
in the study after going through the information sheet, written participants for BLLs and the group studied. Overall, 56 (93.3%)
consent was obtained. A unique code was assigned to each participants in Group 1, 46 (76.6%) participants in Group 2,
participant. The participants were interviewed according to the and 28 (46.6%) participants in Group 3 had BLLs >5 µg/dL
interview schedule, and blood sampling was conducted after the of blood. The BLL ranged from 2.15 µg/dL to 19.03 µg/dL.

DOI: https://doi.org/10.36922/jctr.23.00130