UK Legal Limit
0.05 mg/L
WHO Guideline
0.08 mg/L
EU Standard
0.05 mg/L
Primary Sources
Geology, old iron mains
Manganese in UK drinking water is regulated at 0.05 mg/L. The WHO guideline is 0.08 mg/L and the EU standard is 0.05 mg/L. Manganese is a common cause of brown or black discoloured water in the UK. The WHO lowered its guideline in 2022 due to neurological concerns in children.
At elevated levels, manganese can affect the developing nervous system. Studies have linked high manganese exposure in drinking water to reduced cognitive function, learning difficulties, and behavioural problems in children. In adults, chronic overexposure can cause manganism — a condition with symptoms resembling Parkinson's disease, including tremors, difficulty walking, and mood disturbances. The WHO lowered its guideline value in 2022 to reflect these neurological concerns.
Manganese enters UK drinking water primarily through natural dissolution from rocks and soils into groundwater. Levels tend to be higher in groundwater sources than in surface water. Old cast iron distribution mains can also release manganese that has accumulated over decades as biofilm deposits, particularly when flow patterns change or mains are disturbed. Seasonal changes in reservoir water chemistry can mobilise manganese from sediments.
| Jurisdiction | Limit / Guideline | Notes |
|---|---|---|
| UK (DWI) | 0.05 mg/L | Regulated under the Water Supply (Water Quality) Regulations 2016 |
| WHO | 0.08 mg/L | World Health Organization Guidelines for Drinking-water Quality |
| EU | 0.05 mg/L | EU Drinking Water Directive (2020/2184). The UK no longer automatically mirrors EU standards post-Brexit. |
Reverse osmosis
A membrane filtration process that removes up to 99% of contaminants by forcing water through a semi-permeable membrane under pressure. Highly effective but produces some wastewater.
Ion exchange
Replaces unwanted ions (such as nitrate or lead) with harmless ones using resin beads. Effective and widely used in both whole-house and point-of-use systems.
Activated carbon
Porous carbon material (from charcoal or coconut shell) that adsorbs contaminants as water passes through. Best for organic compounds and some heavy metals.
No filter we list names manganese specifically. Reverse osmosis is shown because it rejects dissolved contaminants broadly rather than by name. Check your own report before buying.
Waterdrop G3P600 Reverse Osmosis
Reverse Osmosis · NSF/ANSI 58, NSF/ANSI 372
Typical price
£550approx.
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Waterdrop 10UA Under Sink
Under-Sink Filter · NSF/ANSI 42
Typical price
£75approx.
Affiliate link: we may earn a commission at no extra cost to you.
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