The study measured the concentration of coarse particulate matter (PM 10) in the ambient air of Bangladesh Small and Cottage Industries Corporation (BSCIC) Bagerhat in order to evaluate its impact on workers’ health. 14 known-volume air samples were obtained through Envirotech APM 541 PM10 Particulate Sampler. The short-term (6 hours) samples were taken from 9 industrial units in the winter season of October, 2015 to January, 2016. Simple gravimetric analysis showed large variations in concentrations in distinct industrial units. The minimum concentration was found 33.61 μ/m 3 in the outdoor premises of a coconut oil mill and the maximum was found 471.38 μ/m 3 in the house of a rice mill. The pollutant sources were detected as cabinless husking machines and soot from boilers and fryers. A questionnaire survey was conducted to evaluate the mostly occurring symptoms of Chronic Obstructive Pulmonary Diseases (COPD) and bronchoconstriction among workers. The highest prevalence of symptoms of bronchoconstriction (OR = 7.1; 95% CI = 2.3 - 21.9) was found among workers in rice mills and eye disturbances (OR = 2.7; 95% CI = 0.9 - 8.6) had the highest prevalence in coconut mills. Monitoring of air quality, providing personal respiratory prevention and improvement in machineries were required in the study area for a healthy environment.
Bangladesh Small and Cottage Industries Corporation (BSCIC) has been contributing to the promotion and extension of micro to small & medium cottage industries yielding social and economic returns domestically [
Agro-based industries are noted as one of the major stationary sources of air pollution in Bangladesh [
Particulate matter is the major pollutant of concern internationally, as it is in Bangladesh [
Occupational exposure to particulate matter in agro based industrial operations had scarcely come to focus in Bangladesh despite having an agro-based economy. Maximum PM10 concentration in a sugar mill in Kushtia was found 380.339 µg/m3 [
BSCIC is situated beside the Khulna-Bagerhat Sadar Road of Bagerhat District in the Division of Khulna in southwest Bangladesh. Small scale (production capacity around 700 kg/day) rice processing mills, coconut oil manufacturing mills, tin processing mills, biscuit mills and pulse processing mills were chosen for air sampling. The study was conducted in November, 2015 to January 2016 with average temperature ranging from 23˚C to 19˚C. The general directions of the wind in winter are north-westerly over the western Bangladesh [
Under the Environment Conservation Act (ECA), 1995 and the Environment Conservation Rules, 1997, agricultural product processing industries are listed in ORANGE-A Category [
The study was dealt through both quantitative and qualitative data collected primarily.
14 air samples of known volume were taken by Envirotech APM 541 PM10 Particulate Sampler through short term sampling (6 hour) from purposively chosen stations. The known volumes of air sample were weighted in laboratory of Environment Science Discipline, Khulna University, Khulna −9208 by the simple gravimetric method to determine the PM10 concentrations (in µg/m3) in samples and each concentration was calculated into 24 hour Time Weighted Average (TWA).
Based on previous studies and documented eye and pulmonary disturbances due to exposure to PM10, a questionnaire was structured, adopting British Medical Research Council (BMRC) Questionnaire [
MS Excel 2013 and IBM SPSS Statistics v21 software were used for drawing results from the study. Permission was granted to conduct the study from the estate manager of BSCIC, Bagerhat. Every participant was interviewed with his/her prior consent.
Reconnaissance survey revealed that generation of coarse particles initiated from the unloading of raw agricultural products in the mill premises. Then they are threshed, boiled, dried, and carried into mill houses where they were husked, processed and packaged. Some of the raw products needed to be shelled out of coir and fried in the burners. The threshing, pressing and husking machinery in the mill houses were run by electricity or generators. These machines were built poorly and had no coverage or cabin to block husks from flying out. The boiling, frying and baking burners were run by biomass which mostly were agricultural by-products, i.e., grain husks, straws, twigs and coconut shells. A few burners were fueled by charcoal. Workers upload charcoal and biomass into the burners by throwing them in and doing so they were exposed to a cloud of dust and soot around them. The mills each have stacks of only about 25 feet height emitting plume where it should be at least 50 feet, as suggested by DoE. The stacks being closer to ground may increase the risks of concentrated particulates in ambient air. The whole mill house remained in the dusty condition in the working time, i.e., from 8 am to 12 am and from 2 pm to 6 pm due to poor ventilation.
The rice and coconut processing mills each had two distinct working zones, indoor mill houses and outdoor drying premises, while the biscuit mill, tin mill, pulse processing mill and BSCIC office had single zone in each. The concentrations found in each zone varied widely and it is shown in
The walk-through survey revealed that 52% of the total sample population was using only a piece of cloth as a mask or gloves. Interviews found out that 86% of the total of them is unaware of any health impact of the dusty environment they were working in and 12% stated that the PPE they were using were inefficient and insufficient. 5% of them felt it was uncomfortable to use masks and gloves due to the hot and humid weather.
Name of the Mill | Selected Zone | Concentration of PM10 (µg/m3) for 24 hour TWA | NAAQS in Ambient air (µg/m3) for 24 hour TWA |
---|---|---|---|
Papon Coconut Oil Mill | Premises | 45.83 | 150 |
Mill house | 157.49 | ||
Akash Coconut Oil Mill | Premises | 33.61 | |
Mill house | 114.10 | ||
Al-amin Rice Mill | Premises | 78.32 | |
Mill house | 390 | ||
Tila-Shila Rice Mill | Premises | 82.42 | |
Mill house | 438.33 | ||
Hossain Rice Mill | Premises | 88.21 | |
Mill house | 471.38 | ||
BSCIC Office Premises | - | 86.49 | |
Pinky Pulse Processing Mill | - | 108.46 | |
Adorsho Tin Mill | - | 52.86 | |
Biscuit Mill | - | 71.31 |
Presented in
On the other hand, the mostly occurred (in 40% of workers of mill house) disturbance among coconut oil mill workers was found to be eye irritation and inflammation as shown in
In
Extracts of airborne grain dust are capable of muscle contraction and narrowing air of air-passage resulting in asthma-like syndrome [
65% of the rice mill workers had frequent sneezing which might have occurred from the entry of coarse particles in the upper trachea, as shown in
Zone | Eye Irritation/ Inflammation (%) | Shortness of Breath (%) | Tightness in chest (%) | Arrhythmia (%) | Dust Allergy (%) | No disturbance (%) |
---|---|---|---|---|---|---|
Premise | 40 | 7 | 0 | 7 | 0 | 46 |
Mill House | 42 | 16 | 0 | 0 | 23 | 19 |
Zone | Eye Irritation/ Inflammation (%) | Shortness of Breath (%) | Tightness in chest (%) | Arrhythmia (%) | Dust Allergy (%) | No disturbances (%) |
---|---|---|---|---|---|---|
Premise | 35 | 15 | 0 | 11 | 0 | 39 |
Mill House | 40 | 25 | 0 | 22 | 0 | 13 |
Eye Irritation/ Inflammation (%) | Shortness of Breath (%) | Tightness in chest (%) | Arrythmia (%) | Dust Allergy (%) | No Disturbance (%) |
---|---|---|---|---|---|
0 | 11 | 22 | 22 | 0 | 45 |
Meanwhile, the differences of symptoms in workers of coconut mills from the unexposed group were significant for eye irritation or inflammation (OR = 2.7; 95% CI = 0.9 - 8.6).
Agro-industries have extremely diverse zone and the contents of particulates depend on where, when and how the dust is produced. The outer premises had sufficient ventilating and dispersing opportunities unlike the mill house. PM10 concentrations were found much denser than the safe limit due to dust emissions
Symptoms associated with | Exposed (n = 21) | Unexposed (n = 50) | OR (95% CI)* |
---|---|---|---|
Eye irritation or inflammation | 9 | 10 | 3.0 (0.9 - 9.1) |
COPD | 7 | 9 | 2.3 (0.7 - 7.3) |
Bronchoconstriction | 14 | 11 | 7.1 (2.3 - 21.9) |
*Odds ratio (95% confidence interval).
Symptoms associated with | Exposed (n = 20) | Unexposed (n = 50) | OR (95% CI)* |
---|---|---|---|
Eye irritation or inflammation | 8 | 10 | 2.7 (0.9 - 8.6) |
COPD | 6 | 9 | 1.9 (0.6 - 6.3) |
Bronchoconstriction | 6 | 11 | 1.5 (0.5 - 4.824) |
*Odds ratio (95% confidence interval).
from husking and packaging machines in the closed hall of rice mills. In a study, enclosed-cabin threshing and husking machines were suggested for such context [
Eye disturbances (OR = 2.7; 95% CI = 0.9 - 8.6) had the highest occurrences in coconut mills, though the concentrations of PM10 were within the standard. However, it could occur due to the cumulative effect of stack gas emission from coconut fryers fueled by biomass with charcoal soot from burners. Visibility impairment due to brown cloud from PM10 emission has been documented [
Threshold limits or exposure limits for mineral or organic PM concentrations do not exist yet due to the difficulties to characterize the PMs found in the agricultural products. The technology used is not advanced and engineering controls are very weak in agro-industrial facilities, resulting in the excess amount of dust [
BSCIC, Bagerhat is the largest diversified agro-industrial complex of the South- east Bangladesh. The investigation was conducted to evaluate PM10 concentration and the effect of its chronic exposure in the workers. PM10 concentrations found in rice mill houses exceeded the threshold limit of the standard. The highest percentages of symptoms of COPD and bronchoconstriction were found in the mill house workers there. The monitoring system of DoE was found ineffective in the area. The BSCIC, Bagerhat authority should supply the workers with dust masks for personal prevention along with providing technical improvements such as water sprinkling system and closed or covered outlets in machinery. Occupational exposure to dust in the agro-industries should be an important area of interest.
The study would not be completed without the provision of equipment and expertise from Environmental Science Discipline of Khulna University. The BSCIC estate manager, Dilip Kumar Sarkar allowed the researchers to step in the industrial complex in its usual scenario and helped willfully in the investigation. We express gratitude to him. The BSCIC workers and residents were very cooperative in the study and the interviews were held with their prior consent.
Roy, S., Hassan, N. and Haider, K.B. (2017) Measurement and Impact Assessment of PM10 in Ambient Air of BSCIC Bagerhat. Open Journal of Air Pollution, 6, 93-102. https://doi.org/10.4236/ojap.2017.63008