Chromium
Chromium is a natural element found in rocks, plants, soil, animals, and volcanic dust and is vital to the environment and human health. It presents itself in various forms, with trivalent chromium Cr3+ and hexavalent chromium Cr6+ being the most common in natural water sources. Trivalent chromium Cr3+ is an essential nutrient in many food items, including vegetables and fruits to meats and grains, for essential bodily functions. Hexavalent chromium Cr6+ stems from environmental deposits and can enter water sources through erosion. Public health issues focus on the occurrence of hexavalent chromium Cr6+ and total chromium, which is identified as a carcinogen to humans.
Water contamination by Chromium
Total chromium, a combination of both trivalent chromium Cr3+ and hexavalent chromium Cr6+, is regulated under the Safe Drinking Water Act for common public health. Since 1991, the national primary drinking water regulation has set the maximum contaminant level (MCL) for total chromium at 0.1 milligrams per liter, guided by maximum contaminant level goals (MCLGs) for chromium water treatment through various water filtration technologies like Reverse Osmosis System. The non-enforceable maximum contaminant level goals (MCLGs) are defined as possible health risks from exposure over a lifetime. However, the exact chromium contamination level in drinking water and chromium in water side effects are likely to be identified.
Health risks associated with elevated Chromium levels
Exposure to high levels of chromium, particularly hexavalent chromium 6 in water, can lead to serious health concerns. Long-term consumption of contaminated water can cause skin irritation and allergic dermatitis (skin reactions) and has been found to be responsible for an increased risk of lung, nasal, and sinus cancers. Chromium has also been affecting severe male reproductive abnormalities, low sperm count, and infertility concerns.
Epidemiological studies have some observations that show a correlation between Cr6+ ingestion and an increased risk of stomach cancer. Animal studies have shown that Cr6+ in drinking water can induce tumors in the alimentary tract, with particularly linear and supralinear responses in the mouse small intestine.
In neutral pH conditions, chromate, the dominant form of Cr6+, enters cells through sulfate channels and undergoes activation by ascorbate and small thiols present in the body, leading to its toxic effects. Ingesting high amounts can also result in stomach issues, ulcers, and liver and kidney damage, emphasizing the need for cautious water quality monitoring and chromium water treatment for healthy, contamination-free drinking water to prevent health issues.
Types of Chromium treatment techniques
Hexavalent chromium in total chromium form, is one of the most toxic forms that require careful chromium removal from water before consumption. Its contamination comes in an odorless and tasteless form that makes it difficult to remove by basic or traditional filter techniques.
Advanced treatment techniques like Reverse Osmosis, ion exchange, and chemical precipitation effectively remove chromium from water. These processes target trivalent chromium Cr3+ and hexavalent chromium Cr6+, ensuring the water is safe for drinking and meets regulatory standards of the Safe Drinking Water Act.
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Reverse Osmosis (RO) systems:
Reverse Osmosis System helps to remove up to 99% of contaminants to make healthier drinking water. ROs are the most effective way for chromium removal from water from a home water supply or water source. A modern RO system uses the sediment pre-filter unit to remove particulates, turbidity, sand, and rust. Then, an activated carbon pre-filter is placed to remove the chlorine, herbicides, pesticides, disinfectants, and Volatile Organic Chemicals (VOCs), which is followed by a reverse-osmosis membrane to remove heavy metals, lead, salt, chromium, and dissolved solids. Using these multiple stages for purification, the RO system removes almost all water contaminants. Reverse Osmosis System comes in multiple variants, such as countertop filters and under-counter reverse osmosis water filtration systems suitable for different needs for home uses. It is beneficial to get an RO system installed in your kitchen to prevent high levels of chromium contamination from your drinking water and keep your family healthy.
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Ion Exchange Method
The ion exchange method is another way of chromium water treatment that can remove chromium 6 from the source water. The ion exchange unit is also known as a water softener that uses tiny resin beads packed tightly inside the columns to filter out the ionic minerals and other contaminants from source water. However, this is a less effective and value-for-money method than RO systems. On the contrary, it requires regular maintenance and cleaning. However, Reverse osmosis filters paired with a water softener can be a very effective water filtration combination for drinking water.
Preventing Chromium contamination
Natural water can be used (reused) multiple times for various uses with traditional filtration methods. However, the effluent from various industries makes it challenging to reuse water that goes into water sources and contaminates it. To prevent chromium contamination in water, industries must adopt stringent wastewater management practices and strict norms. Implementing closed-loop systems in metal plating, upgrading filtration in tanneries, and utilizing eco-friendly dyes in textiles are helpful methods. The introduction of bioremediation techniques and the integration of advanced oxidation processes can also degrade non-biodegradable chromium compounds, preventing their accumulation in the ecosystem. Rigorous monitoring and adherence to environmental regulations will mitigate chromium's carcinogenic risks and its bioaccumulation in the food chain and drinking water sources.
Conclusion
Chromium water treatment is essential for healthy and contamination-free drinking water to ensure safety from harmful impacts on human health and the ecosystem. Installing Reverse Osmosis (RO) filters at home is an advanced water purification technology that provides an efficient and reliable method for chromium removal from water. RO systems not only purify water but also instill confidence in the quality of water we use daily in our kitchen.