Cement Dust - Effects of Pollution on Human Health Essay
Introduction
Air pollution is a major problem in many countries of the world and emerging evidence suggests that environmental factors play an influential role in shaping human-associated microbial communities and immune responses. Several epidemiological studies have indicated a strong association between cement dust and lung cancer, asthma and other allergic reactions. Indeed, environmental toxicants have been found to alter epigenetic regulatory features such as DNA methylation, and non-coding RNA expression in the host and his associated microbiomes. Here is “effects of pollution on human health essay” where it will be considered what health problems polluted air brings.
Cement dust is a major particulate air pollutant which has been shown to cause negative effects on plants growth and development. Cement dust exposure constitutes a variety of negative impacts on human health, global climate change, agricultural productivity and the natural ecosystem. There is good evidence for cement dust exposure acting in the same way as tobacco, alcohol and independent risk factors for laryngeal carcinoma with the main route of entry being inhalation or swallowing through the respiratory tract or gastrointestinal tract respectively. Its deposition in the respiratory tract causes a basic reaction leading to increased pH values that irritates the exposed mucous membrane.
The increased activities in cement plants and factories contribute great impact in the emissions of air pollutants over the years in Nigeria.The dust escaping from cement factories is often transported by wind and deposited in areas close and far away from the factory. Such depositions of particulate matter and other pollutants interfere with normal metabolic activities of human beings and they also cause diseases such as cardio-respiratory disease, low birth-weight, and exacerbation of asthma especially in children or death.
The human microbiome is a collection of genomes of microbiota, namely protozoa, archaea, eukaryotes, viruses and predominantly bacteria that live symbiotically on and within various sites of the human body. Examples of occupied habitats include the oral cavity, genital organs, respiratory tract, gut, skin and gastrointestinal system. The oral microbiome is defined as the collective genome of microorganisms that reside in the oral cavity. It is the second largest microbial community in humans after the gut microbiome and they exhibit astounding diversity of predicted protein functions when compared with other body sites.
The human microbiome has the stability and resilience to restore itself after perturbation to maintain homeostasis in health, but its composition is susceptible to many environmental factors such alcohol, smoking and other air pollutants. The structure of the oral microbial community which includes a range of structural and functional configurations changes in the abundance of certain taxa and the concurrence of certain microbes. Changes in the populating microorganisms ensure individual acquires certain microbiota stability of which depends on compensation mechanisms ensuring suitable condition in the mouth cavity. However, other factors such as unsuitable diet can irreversibly affect thr homeostasis of the oral ecosystem and subsequently leads propagation of pathological changes in the oral cavity.
Cement Dust and Microbiome Perturbation
It has been shown that cement dust is a major environmental challenge in many developing countries. Airborne particulate matter (PM) from this dust is especially detrimental to health, and has previously been estimated to cause between 3 and 7 million deaths every year, primarily by creating or worsening cardio-respiratory disease. Particulate sources in Nigeria include cement plant and quarries where certain chemicals such as calcium oxide, silicon oxide potassium oxide, magnesium oxide, and other toxic heavy metalsand chemicals (such as lead, cadmium, chromium, etc.) are produced.
The oral microbiome is in continual contact with the environmental and has been shown to be susceptible to many other environmental effects which include tobacco use, romantic partners and cohabitation. Cement dust exposure is also one key environmental effect that influence the oral microbiome. Ecosystem in the mouth can become disturbed causing a dysbiotic shift and loss of microbial community balance. Some of these chemical agents in cement dust are genotoxic and may cause genetic alterations in the somatic or germ cells of exposed individuals and such alterations may lead to the development of cancer and other health risks.
Changes to microbial ecology can affect the functionality of the oral microbiome and equally, loss of necessary functional properties from oral microbes that are essential in maintaining health may induce changes to the oral microbial composition, and these changes can induce disease. Some oral microbiomes were associated with lower lung function and disease with periodontitis. Lower respiratory infection begins by contamination of the lower airway epithelium by aspiration of oral secretions containing bacteria. Respiratory pathogens and the shedding of attached bacteria from these sources into contiguous secretions subsequently contaminate the lower respiratory tract. Several epidemiological studies have also found results favoring the role of oral bacteria in the pathogenesis of respiratory diseases.
Genomic Perturbation
Cement dust inhalation is associated with deleterious health effects and the toxic effects of most elements in the dust depend principally on the absorption, concentration and persistence of the elements in the site of action. These elements reacts with the endogenous target molecule such as enzymes, DNA, proteins and lipid and critically alter their biological functions, producing structural and functional changes that result in toxic damage.
Microelement elements in cement dust such as chromium are considered carcinogenic and there has been a strong association between exposure to cement dust and laryngeal carcinoma acting similarly to tobacco, alcohol and asbestos. In addition, an increased activity of the antioxidant enzymes and depletion of total antioxidant capacity indicate that exposure to cement dust leads to increased oxidative stress.
Inflammatory reactions and carcinogenesis in the alveoli and bronchi have also been associated with prolonged to exposure to Cr(VI) and crystalline silica from cement dust. Studies have also shown that construction workers showed a significant increase in micronucleus and comet tail length which is an indication that exposure to cement during construction work could lead to increased levels of DNA damage and repair inhibition. Other genetic damages comprised of minor chromosomal aberrations, decrease in mitotic index and increased frequency of sister chromatid exchanges.
Exposure to diesel exhaust particles from cement factory, cigarette smoke and ozone has been reported to cause epigenetic changes in the respiratory tract, which have been implicated in the development of inflammatory lung diseases. DNA methylation and histone modifications are thought to be the major epigenetic mechanisms leading to transcriptional silencing of genes relevant to the development of airway inflammatory and allergic diseases following environmental exposures.
Several studies carried out in workerswho were exposed to air pollutants showed there was altered methylation of tumor suppressor genes (APC, CDKN2A, MLH1). Alterations to the cellular methylation systems are thought to be associated with inflammatory reactions that can be triggered by the inhalation of airborne pollutants. These perturbations to the DNA methylation machinery may be part of a cellular adaptive response mediating the environmental effects of pollution on human health.
Immune Markers
Exposure to silica can result in or contribute to several other diseases including acute silicosis, pulmonary tuberculosis, interstitial fibrosis, rheumatoid complications, vascular diseases, glomerulo nephritis, and immunological reactions. Though inflammatory responses resulting from workplace exposures are usually observed in specific target organs, such as the lungs, skin and liver and if persistent, may progress to fibrosis, granulomatous diseases and even cancer. On the basis of new knowledge, it is possible that cement dust may have effects on the immune and liver functions. Increased levels of different immunoglobulin classes have been reported in previous studies on the effects of silica on immunoglobulin classes.
Immunoglobulin tests may be useful new parameters in assessing and monitoring the health of cement workers in addition to the traditional biochemical tests and genotoxic changes. The complex cellular interactions involving cells of the immune system, inflammatory and haematopoietic systems evolved to protect vertebrates from foreign invaders. Significant higher IgE causes allergy response in workers exposed to cement dust, which if persistent may result in systemic anaphylactic reaction. The increased IgG along with IgE probably support the hypothesis that allergen immunotherapy inhibits allergy, in part, by inducing production of IgG antibodies that intercept allergens before they can crosslink mast cell FceRI-associated IgE.
Studies have suggested that in the cement factory, where the workers are exposed to cement and other dusts, there are insignificant in liver function test but significant immunoglobulin classes changes which need to be elucidated so that the aftereffects of toxicant contamination may be monitored and eliminated. Also the humoral immune system might be exacerbated if the exposure to this dust is not controlled.
Problem Statemnt
We know that cement dust is a potent cause of occupational related respiratory and other diseases, and there is abundant literature both in Nigeria and elsewhere. A study carried out on the workers of cement factory in Kalambaina (Sokoto) revealed that cement dust was deleterious to health of the workers. Many other studies have elucidated the occupational hazards of cement dust and its effects on human health, for instance in oral diseases such as periodontitis. It has also been identified as a skin allergen, eye and respiratory tract irritant and implicated in dyspnea, chronic bronchitis and other lung function impairment in workers exposed to particulate concentration. However, information about the effect of cement dust on the genetic and oral microbiome perturbation in Nigeria cement plants’ receptor environment is quite limited in the literature.
Conclusion
Cement dust contains oxides, many toxic heavy metals and chemicals and particulate matters. The dust emitted in form of particulate matters degrades the air quality and create considerable environmental pollution. Many of these air pollutants have been associated with increased respiratory and skin infections among individuals residing near cement manufacturing industry.
Growing urbanization in developing country such as Nigeria creates ever-increasing needs for cement. The cement industry holds some advantages that can allow it to meet this demand. It is one of the most important primary and basic industries and key factor in economic development. It contributes importantly to the development of other factories and creation of employment opportunities. Indeed, the increasing demand for cement and associated products in Nigeria makes it necessary for detailed investigations into the genetic health risk of cement dust exposure.
