Environmental Issues and Health Effects

Learning Outcomes:

1. Understand the impact of toxic pesticides on the environment and health.
2. Recognize various diseases caused by environmental degradation.
3. Identify the significance of energy drinks, transfats, and lead in paints on human health.
4. Explore different movements and initiatives for environmental conservation.
5. Gain knowledge of various international standards for environmental management.

Persistent Toxic Pesticides

Toxic pesticides like DDT, BHC, and PCB are difficult to degrade and persist in the environment. These substances accumulate in water and soil, leading to higher concentrations with repeated use. DDT was widely sprayed to control mosquitoes, but its bioaccumulation in the food chain caused devastating health effects.

1. DDT’s Bio-magnification: Fish-eating birds and humans ingest DDT through the food chain, causing mortality in fish, turtles, and predatory birds.
2. Hormonal Impact: DDT depresses estrogen and testosterone activities, affecting reproductive health.
3. Infant Risks: DDT in butterfat poses severe health hazards to infants.
4. Bird Vulnerability: DDT disrupts eggshell formation, leading to fragile eggs and a decline in bird populations like ospreys.

Lead in Paints

Despite its toxicity, lead remains a common component in paints due to economic and performance considerations, particularly in countries like India.

1. Health Hazards: Inhaling lead dust during activities like opening windows can lead to poisoning.
2. Vulnerability of Children: Lead exposure severely affects children’s central nervous systems and brains.
3. Why Lead Persists in Paints: Alternative substances are costlier and reduce paint performance, causing manufacturers to continue using lead.

Transfats and Their Health Effects

Transfats are produced by adding hydrogen to oils, giving products a longer shelf life but posing serious health risks.

1. Formation and Usage: Created during hydrogenation, transfats help prevent oils from becoming rancid.
2. Associated Health Issues: Linked to diabetes, heart disease, and cancer.
3. Junk Food: High transfat, salt, and sugar content in junk food contributes to hypertension, obesity, and other health problems.

High Caffeine in Energy Drinks

Energy drinks are under scrutiny due to their high caffeine levels, affecting consumer health and wellbeing.

1. Caffeine Content: Some energy drinks contain up to 320 ppm of caffeine, exceeding recommended limits.
2. Energy Sources: Manufacturers attribute energy boost to caffeine, taurine, vitamins, and sugar, but studies show sugar as the main energy source.
3. Regulatory Issues: Despite amendments to limit caffeine in drinks, market regulation remains weak, allowing continued proliferation.

Pesticide Contamination in Human Blood

The widespread use of pesticides in agriculture has led to their presence in human blood, especially in rural areas.

1. Blood Contamination: Studies in India revealed the presence of 15 different pesticides in blood samples from rural populations.
2. Accumulation: Pesticides like organochlorines accumulate in body fat, persisting for years and posing chronic health risks.

Important Note: LD 50 (Lethal Dose 50) is a standard measure of acute toxicity. The lower the LD 50 value, the more acutely toxic the substance. For instance, DDT’s LD 50 is 113 mg/kg, while monocrotophos, another pesticide, has an LD 50 of 14 mg/kg, indicating higher acute toxicity.

Diseases Caused by Environmental Degradation

Various diseases are linked directly to environmental pollution and degradation, resulting in widespread health issues.

1. Minamata Disease: Caused by methyl mercury from industrial wastewater in Japan; symptoms include muscle weakness, vision and hearing loss, and in severe cases, insanity and death.
2. Yokkaichi Asthma: Resulting from sulfur oxide smog due to petroleum burning in Japan, causing chronic respiratory conditions.
3. Itai-itai Disease: Stemmed from cadmium poisoning due to mining, leading to bone softening and kidney failure.
4. Blue Baby Syndrome: High nitrate levels in groundwater from agricultural runoff reduce hemoglobin’s oxygen-carrying capacity in infants, leading to mortality.
5. Pneumoconiosis: Coal miners suffer from lung disease due to inhaled coal dust, commonly known as black lung disease.
6. Asbestosis: Workers in the asbestos industry develop this lung disease from prolonged asbestos exposure.
7. Silicosis: Silica deposits in workers’ lungs in industries like sandblasting result in severe respiratory problems.
8. Emphysema: The breakdown of lung tissues due to cigarette smoke and air pollution limits lung expansion.
9. Sick Building Syndrome (SBS): A combination of ailments linked to poor indoor air quality, HVAC system flaws, and contaminants from building materials.

Environmental Movements

The Chipko and Appiko movements are notable examples of grassroots efforts to protect forests and promote environmental conservation.

1. Chipko Movement: Started in the 1970s in the Garhwal Himalayas; involved hugging trees to prevent deforestation. The actions of local women inspired widespread conservation efforts across India.
2. Appiko Movement: Inspired by Chipko, the Appiko movement emerged in Karnataka in 1983 to save forests, expanding awareness in southern India.

International Standards for Environmental Management

ISO 14000 series provides guidelines for managing environmental impacts of organizations, focusing on compliance and continuous improvement.

1. ISO 14001: Details requirements for an environmental management system.
2. ISO 14020 Series: Addresses environmental labels and declarations for products.
3. ISO 14031: Provides guidelines for evaluating environmental performance.
4. ISO 14064: Outlines methods for measuring, quantifying, and reducing greenhouse gas emissions.

Key Environmental Conservation Concepts

Flagship, keystone, indicator, foundation, umbrella species, and charismatic megafauna are categories used in conservation strategies.

Important Note: Loss of a keystone species can lead to significant ecosystem changes, affecting various dependent species and the overall biodiversity.

The National Wastelands Development Board (NWDB)

Set up in 1985 under the Ministry of Environment & Forests, NWDB’s objective was to increase green cover on wastelands and prevent land degradation.

1. Objectives: Enhance tree cover, prevent land degradation, and develop management plans for wastelands.
2. Transition: In 1992, NWDB was transferred to the Ministry of Rural Development, focusing on broader land management.

Bioassays

Bioassays are crucial in detecting environmental disturbances and pollutants through the reaction of organisms to various toxicants.

1. Definition: A test involving organisms to detect the presence or impact of physical or chemical factors.
2. Applications: Common in pollution studies; fish and insect bioassays help in determining the safe concentration of chemicals.

Additional Important Concepts

1. Reforestation and Afforestation: Reforestation involves restocking depleted forests, while afforestation refers to planting forests in areas without prior tree cover.
2. Eutrophic Lakes: High nutrient content leads to algal blooms and poor water quality, unlike oligotrophic lakes with low productivity and clear waters.
3. Bioleaching: A cleaner method of extracting metals using living organisms, reducing environmental impact compared to traditional techniques.

Important Note: Eutrophication increases Biochemical Oxygen Demand (BOD), causing oxygen depletion in water bodies and leading to the death of aquatic organisms.

Glossary of Key Terms

1. Warm-blooded: Animals maintaining constant body temperature internally, like mammals and birds.
2. Aestivation: A state of dormancy in response to high temperatures and arid conditions.
3. Deforestation: Removal of forests leading to land conversion for non-forest uses, causing biodiversity loss.
4. Carbon Footprint: Measurement of greenhouse gas emissions by an individual or organization, expressed in CO₂ equivalents.

Important Note: Carbon Credits are part of efforts to mitigate greenhouse gas emissions, where one credit equals one metric ton of CO₂ equivalent.

Multiple Choice Question: Which of the following describes the process of bioassay?

1. A method of reforestation in degraded lands.
2. Testing organisms for detecting the effects of environmental disturbances.
3. An international standard for managing environmental impact.
4. Conservation

movement to protect endangered species.

Correct Answer: 2. Testing organisms for detecting the effects of environmental disturbances.