A Partial LIst Of The Environmental Laws/Rules UK Has Dropped Since Brexit. It's Long.
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Chemical regulations
Law change: The UK has left the EU chemical regulation body, called EU Reach, which works quickly to ban substances found to be toxic to human health. After Brexit, the UK started its own smaller version, called UK Reach. Eight rules restricting the use of hazardous chemicals have been adopted by the EU since Brexit, and a further 16 are in the pipeline. The UK, however, has not banned any substances in that time and is considering only two restrictions: on lead ammunition, and harmful substances in tattoo ink.
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Pesticides
Law change: The UK has not banned 36 harmful pesticides that have been proscribed for use in the EU. Thirty of the 36 were allowed for use in the EU when the UK left on 31 January 2020 but have since been banned by the bloc, and the remaining six have been approved by the UK government but not the EU since then. The best-known of these pesticide is thiamethoxam, a neonicotinoid that is highly toxic to bees and can remain in the soil long after treated seeds are planted. The UK has permitted its use every year since Brexit, while the EU has banned it.
What it means: These pesticides are mostly banned for the harm they do to the environment and the insects, fish and other animals that live within it. It means farmers in the UK can use products that have been shown to harm invertebrate and insect populations.
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Deforestation
Law change: The EU has legislated to remove deforestation from its supply chain for products including wood, rubber, beef, leather, cocoa, coffee, palm oil and soy, meaning products will not make it into the bloc unless they can be shown to be deforestation-free. The UK’s recently announced scheme applies only to illegal deforestation, and leaves out some popular products including coffee.
What it means: Critics have said that the UK scheme has a “perverse incentive” for countries to legalise deforestation, as only products created as a result of illegal deforestation fall under the ban. Regardless of this, it means products imported into the UK can be causing devastating deforestation, even if not illegal.
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https://www.theguardian.com/environment/2024/jan/19/the-uk-environmental-protections-dropped-since-brexit