Abstract

INTRODUCTION

Nearly a century after Mahatma Gandhi first called for the abolition of manual scavenging, the degrading practice continues. Between 2002 and 2003, the Indian Ministry for Social Justice and Empowerment admitted to the existence of 676,000 scavengers.[1] However, these figures may have been underestimated because scavenging is illegal. According to one survey by Bezwada Wilson of the Safai Karmachari Association, an estimated 12 lakh (1.2 million) scavengers are present in the country.[2] According to Sulabh, four to five million people were working as scavengers in 2005 and were often employed by the local civil bodies to clean excrement in public places.[1] This situation persists despite the fact that the Employment of Manual Scavengers and Construction of Dry Latrines (Prohibition) Act,[3] 1993, is in enforcement, which provides for the prohibition of the employment of manual scavengers as well as construction or continuance of dry latrines and for the regulation of construction and maintenance of water-seal latrines for assuring the dignity of the individual, as enshrined in the Preamble to the Constitution.

The working conditions of the sanitary workers have remained virtually unchanged for over a century. Using only a stick broom and a small tin plate, the sanitary workers clear feces from public and private latrines onto baskets or other containers, which they then carry on their heads to dumping grounds and disposal sites. A few, however, are provided with wheelbarrows or carts by the municipal authorities.

Apart from the social atrocities that these workers face, they are also exposed to certain health problems by virtue of their occupation. These health hazards include exposure to harmful gases, cardiovascular degeneration, musculoskeletal disorders, infections, skin problems and respiratory system problems.

EXPOSURE TO HARMFUL GASES

The workers are commonly exposed to gases like hydrogen disulfide, methane, ammonia and carbon monoxide. Watt et al.[4] studied 26 sewer workers exposed to smell and found that 53.8% developed sub-acute symptoms including sore throat, cough, chest tightness, breathlessness, thirst, sweating, irritability and loss of libido. Severity of symptoms seemed to be dose related. Richardson[5] studied exposure to hydrogen sulfide in 68 sewer workers and found that the FEV₁/FVC values were lower in sewer workers who had a high H₂S exposure.

MUSCULOSKELETAL DISORDERS

Osteoarthritic changes and intervertebral disc herniation are the common spinal abnormalities reported in these workers.[6] Friedrich[7] studied 255 sewage workers to determine the prevalence of spinal troubles (i.e., neck, upper back and lower back pain [LBP]). He reported that the 12-month prevalence rates of neck, upper back and LBP were 52.4%, 54.8% and 72.8%, respectively. The prevalence of spinal troubles increased with age. Work disability during the preceding 12 months due to LBP was significantly positively associated with age, disability, weekly duration of stooping and lifting 5 years previously and higher abnormal illness–behavior scores (odds ratio between 1.26 and 0.94).

INFECTIONS

The modes of exposure for the various infections are as follows:

• The most common way is by hand-to-mouth contact during eating, drinking and smoking, or by wiping the face with contaminated hands or gloves or by licking splashes from the skin.
• By skin contact, through cuts, scratches or penetrating wounds, i.e., from discarded hypodermic needles. Certain organisms can enter the body through the surfaces of the eyes, nose and mouth.
• By breathing them in as dust, aerosol or mist.

The infections commonly studied among this group of workers include leptospirosis, hepatitis and Helicobacter pylori infection.

DERMATITIS

Mostly, the dermatitis is a non-infective one. It results from irritation to mineral oil and tar. An outbreak of cases of airborne irritant contact dermatitis has been reported among incinerator workers employed in a sewage treatment facility.[19]

RESPIRATORY SYMPTOMS AND FUNCTION

Several studies have been carried out to study the respiratory function of sewage workers, with all of them reporting that respiratory symptoms are common[20–22] among this group of workers. The respiratory function studies also revealed abnormal respiratory functions in these workers. These symptoms may be due to exposure to endotoxins and airborne bacteria by way of bioaerosols. Zuskin et al. reported that the baseline ventilatory capacity was significantly decreased compared with the predicted values in sewage workers. In particular, the values for FEF_{25 -50} were reduced,[23] suggesting obstructive changes in smaller airways. They mentioned that sewage workers are exposed to different occupational noxious agents, which may lead to the development of chronic lung function changes.[24]

Thus, to summarize, the sewage and sanitary workers suffer mainly from chemical and biological hazards. This can be prevented through engineering, medical and legislative measures. The engineering measure should focus on making the process more mechanistic. These workers should also be benefited from occupational health services, which should include pre-placement and periodic health monitoring. Further effective implementation of the Employment of Manual Scavengers and Construction of Dry Latrines (Prohibition) Act, 1993, will help in the abolition of manual scavenging. Also, regular awareness programs should be conducted to impart education regarding safer work procedures and use of personal protective devices.