Contaminants such as lead, mercury, arsenic, and cadmium can leach into water from natural deposits or industrial activities.
Understanding Common Drinking Water Contaminants
Water that appears clean and clear can still contain a wide range of contaminants that may pose risks to human health. Understanding these risks is the first step toward ensuring safe, high-quality drinking water for your home or property.
Heavy Metals
Contaminants such as lead, mercury, arsenic, and cadmium can enter water supplies through natural geological deposits or industrial activities.
Even at low concentrations, these metals are toxic and may contribute to long-term health issues, including neurological, kidney, and developmental effects.
Agricultural Chemicals
Chemicals used in agriculture can infiltrate water sources through runoff, particularly in rural and farming regions.
Common examples include atrazine and glyphosate, which are widely used herbicides.
These substances have been associated with potential health risks and are of increasing concern in both private and municipal water supplies across New Zealand.
Industrial Chemicals and Solvents
Industrial processes and waste disposal sites can introduce harmful chemicals into groundwater and surface water.
Compounds such as benzene, trichloroethylene (TCE), and other solvents are known to pose both short-term and long-term health risks.
These contaminants are often invisible, odourless, and difficult to detect without proper testing.
Microbiological Contaminants
Microorganisms including bacteria, viruses, and parasites are a leading cause of waterborne illness.
Common pathogens include:
Escherichia coli (E. coli)
Giardia
Cryptosporidium
These organisms can enter water supplies through animal waste, septic systems, or surface contamination, particularly affecting untreated rural water sources.
Emerging Contaminants (Pharmaceuticals & Personal Care Products)
Trace levels of medications, hormones, and personal care products are increasingly being detected in water supplies worldwide.
While typically present in very low concentrations, there is growing concern about:
Long-term human health effects
Environmental impacts on aquatic ecosystems
These substances are not always removed by conventional water treatment systems.
Why This Matters
Many of these contaminants are:
Invisible to the eye
Undetectable by taste or smell
Potentially harmful over time
Without proper filtration and treatment, water that appears safe may still fall short of recommended drinking water standards.
Filtration Canterbury Approach
At Filtration Canterbury, we design tailored water treatment solutions that address these contaminants using proven technologies such as:
Sediment filtration
Activated carbon filtration
Reverse osmosis (RO)
UV disinfection
Specialty media for metals and chemical removal
Our systems are aligned with New Zealand Drinking Water Standards (NZDWS) and designed to deliver safe, reliable water for homes, farms, and commercial applications.
When disinfectants such as chlorine react with organic and inorganic matter in water, they can form disinfection by-products like trihalomethanes.
Disinfectants such as chlorine play an essential role in protecting public health by eliminating harmful microorganisms in drinking water. However, when chlorine reacts with naturally occurring organic and inorganic matter, it can form disinfection by-products (DBPs) such as trihalomethanes (THMs). These by-products are regulated due to their potential long-term health risks, making their management an important part of water treatment.
Chlorine and fluoride are commonly added to municipal water supplies to improve safety and dental health outcomes. While these additives provide clear public health benefits, some consumers have concerns about taste, odour, and the potential effects of long-term exposure.
Nitrates and nitrites, often associated with agricultural activity and fertiliser use, are a significant concern in many regions. Elevated levels in drinking water can pose health risks, particularly for infants and pregnant women, and are linked to conditions such as methemoglobinemia, commonly known as “blue baby syndrome.”
More recently, attention has turned to microplastics in drinking water. These tiny particles have been detected in water supplies worldwide, raising questions about their long-term health impacts and environmental effects. Research in this area is ongoing, but their presence highlights the increasing complexity of water quality management.
Together, these contaminants represent both established and emerging challenges in maintaining safe drinking water. Addressing them requires a combination of accurate testing, appropriate filtration and treatment systems, and adherence to recognised drinking water standards.
