Are cyanobacteria safe for human consumption?

Overview

During the summer, cyanobacteria develop in lakes, ponds, streams, and rivers, changing the color of the water. They occur naturally in aquatic habitats, but excessive nutrient inputs to lakes and rivers are causing their expansion, which has ecological, health, and economic ramifications. This page sheds light on this growing family of bacteria. Due to excessive nutrients, cyanobacteria grow in warm summer lakes and ponds, discoloring the water and posing global ecological, health, and economic issues. This article explains these increasingly important bacteria.

Cyanobacteria in lakes

Essential to Earth's ecosystems

*Photosynthetic cyanobacteria—blue-green algae—are essential to Earth's ecosystems. These ancient life forms produced oxygen through photosynthesis, causing the Great Oxidation Event that changed Earth's atmosphere.

*Chlorophyll, carotenoids, and phycobilins help these bacteria harness sunlight. Prokaryotic cyanobacteria lack nuclei and membrane-bound organelles, unlike algae. They flourish in freshwater, marine, and moist soils as unicellular, filamentous, or colonial organisms.

*Plants need cyanobacteria to fix atmospheric nitrogen. However, some species can generate toxic algal blooms that endanger aquatic ecosystems and humans.

How have cyanobacteria evolved?

*About 3.5 billion years ago, cyanobacteria evolved in ancient waters. These early life forms produced oxygen through photosynthesis and shaped Earth's atmosphere. Cyanobacteria caused the Great Oxidation Event 2.4 billion years ago, modifying Earth's atmosphere and allowing oxygen-dependent life to arise.

*These tiny organisms presumably developed from simpler prokaryotes. They thrived in hot springs, snowy tundras, and marine, freshwater, and terrestrial settings. Their capacity to fix nitrogen and survive severe settings has helped them survive across geological time.

How do they affect the environment?

• Cyanobacteria are important to modern ecosystems, both good and harmful. 
• Cyanobacteria are versatile and distributed worldwide. Some significant areas where they thrive are
• In nutrient-rich lakes, rivers, ponds, and wetlands, cyanobacteria thrive.
• They help fix nitrogen and produce oxygen in the oceans.
• One of the most durable creatures, cyanobacteria can thrive in hot springs, deserts, polar ice, and hypersaline lakes.
• Soil and Rocks: Some species build biological soil crusts, supporting and enriching arid soils.
• Symbiotic Relationships: They share nutrients with plants, fungi, and corals.

The ability to adapt to different situations makes them vital to ecosystems.

• Photosynthesis by cyanobacteria produces oxygen worldwide, just as they did billions of years ago.
• Nitrogen Fixation: They turn atmospheric nitrogen into a plant-usable form, improving soil fertility and agriculture.
• Climate Change Adaptation: Some cyanobacteria can handle rising temperatures and fluctuating nutrient levels.
• Cyanobacteria can generate toxic blooms in lakes and oceans in nutrient-rich circumstances, disrupting aquatic ecosystems and posing health concerns to humans and animals.
• Soil Restoration: Cyanobacteria build biological soil crusts to improve soil fertility and stability.
• This is dangerous to ecosystems. Their ability to adapt to environmental changes makes them both important and dangerous to ecosystems.

How do they affect health?

• Humans and animals are at risk from harmful algal blooms (HABs). 
• Contaminated water can cause rashes, irritation, and burning.
• HAB airborne pollutants can cause coughing, wheezing, and breathing problems.
• Nausea, vomiting, diarrhea, and stomach pain can occur as a result of drinking or ingesting polluted water.
• HABs can create microcystins, which can damage the liver, and neurotoxins, which can cause dizziness, disorientation, or paralysis.
• Threat to Pets and Wildlife: Drinking or swimming in impacted water can poison animals and kill them.
• Seafood contaminated with HABs is dangerous to eat. Following local health recommendations is important because cooking does not eliminate these poisons.

Take these actions to avoid hazardous algal blooms (HABs):

• Before swimming, fishing, or boating, check local health advisories for HAB warnings.
• Stay away from discolored, foamy, smelly, or dead fish-filled water.
• If you come into contact with contaminated water, please rinse off with clean tap water right away.
• Avoid Pets and Livestock: Avoid drinking or swimming in HAB-contaminated water because animals are extremely susceptible.
• It's crucial to abide by local shellfish and fishing advisories because cooking does not eliminate HAB toxins, which can accumulate in seafood.
• Stay clear of HABs that emit airborne poisons that can irritate the lungs.

How are harmful algal blooms (HABs) monitored and controlled?

Also read https://www.maine.gov/dep/water/lakes/cyanobacteria.html

Cyanobacteria are versatile and distributed worldwide. Some significant areas where they thrive are

• In nutrient-rich lakes, rivers, ponds, and wetlands, cyanobacteria thrive.
• They help fix nitrogen and produce oxygen in the oceans.
• One of the most durable creatures, cyanobacteria can thrive in hot springs, deserts, polar ice, and hypersaline lakes.
• Soil and Rocks: Some species build biological soil crusts, supporting and enriching arid soils.
• Symbiotic Relationships: They share nutrients with plants, fungi, and corals.

The ability to adapt to different situations makes them vital to ecosystems.

Several visual and sensory clues indicate harmful algal blooms (HABs). What to look for:

• Depending on the algae, water can be blue, green, brown, yellow, orange, or red.
• Surface changes: HABs can leave scum, foam, matting, or globs on water like paint.
• Algae breakdown releases fumes that smell like rotten eggs or plants.
• Dead Fish or Wildlife: A sudden surge in dead fish or aquatic creatures near the shoreline may signal a poisonous bloom.
• Shoreline algae might be another warning indication.
• Foamy Water: Some HABs cause foam around water bodies.

Some dangerous algal blooms are submerged and release poisons without affecting the water's appearance. If you suspect a bloom, avoid contact and verify local health recommendations.

Cyanobacteria have many uses. Examples of their prominent uses:

• Engineering cyanobacteria to make biofuels is a sustainable alternative to fossil fuels.
• Agriculture: Biofertilizers increase crop yields by supplementing soil with nitrogen.
• They absorb contaminants and heavy metals in wastewater treatment, minimizing environmental contamination.
• Cyanobacteria produce bioactive chemicals with antibacterial, antiviral, and anticancer activities, making them useful in drug research.
• Some species, like spirulina, serve as dietary supplements because of their high protein and antioxidant content.
• Carbon Capture: Cyanobacteria reduce climate change by absorbing CO2.

They're versatile and promising for sustainable solutions.

Cyanobacteria are distinguished by their oxygenic photosynthesis and evolutionary history. They compare

• Cyanobacteria are among the oldest biological forms, stretching back over 3.5 billion years. Their oxygen production fueled Earth's evolution and the Great Oxidation Event.
• Cyanobacteria, unlike most bacteria, do oxygenic photosynthesis like plants. This characteristic distinguishes them from other prokaryotes, which use anoxygenic photosynthesis or different metabolic routes.
• Genetic Adaptations: Genome rearrangements, mutations, and horizontal gene transfer have helped cyanobacteria evolve.
• Cyanobacteria have multicellular structures, including heterocysts for nitrogen fixation, which is rare in bacteria.
• Environmental Impact: Their ability to fix nitrogen and live in severe settings has allowed them to influence ecosystems worldwide across geological time.
• Their development has shaped life on Earth, making cyanobacteria fascinating in microbiology.

How do they affect ecosystems?

Hazardous algal blooms (HABs) can devastate the environment. 

• As algae develop and die, their breakdown absorbs oxygen, generating low-oxygen zones that can smother fish and other aquatic life.
• Water contamination: HABs produce poisons that contaminate drinking water, endangering humans and wildlife.
• Toxins and oxygen depletion can cause huge fish die-offs, affecting aquatic ecosystems.
• HABs can damage fisheries, tourism, and recreation, hurting coastal economies.
• Climate Change: Rising temperatures and nutrient pollution increase HAB prevalence and severity worldwide.

Human activities like agricultural runoff and wastewater discharge are increasing blooms.

The following are some major contributors to the occurrence of harmful algal blooms:

• Algal development is fueled by excess nitrogen and phosphorus from agricultural runoff, sewage, and industrial waste.
• HABs are more frequent in summer and fall because they like warm, slow-moving water.
• Slow water circulation encourages algae to grow.
• Global warming and shifting weather patterns increase HAB frequency and severity.
• Hurricanes, floods, and droughts can cause algal blooms.
• Upwelling: Deep ocean water rising to the top brings nutrients to algae.

These circumstances enable algae to multiply quickly and produce toxins that endanger aquatic life and humans.

If you suspect water contamination, do this:

• Do not drink, cook, or bathe in suspected polluted water.
• Look for Signs: Check water for strange taste, odor, or discoloration. The water may be murky, smell metallic, or have an oily layer.
• If biological contamination is suspected, boil water for one minute to destroy bacteria and viruses. It won't remove chemical contaminants.
• Use Bottled Water: Until the issue resolves, use bottled or filtered water.
• Report Issue: Ask your water utility or health department for a water quality test.
• Keep track of health symptoms. Consult a doctor if you have nausea, vomiting, diarrhea, or skin irritation.
• Get Local Advice: Local authorities may warn of water contamination.

Conclusion

Rapid algae or cyanobacteria development in lake, pond, and river water can affect people, animals, and the environment.  Being in or near dangerous algal blooms can make you and your animals sick.  Avoid water that is discolored, scummy, or smells terrible.