Okay, I need to create a Wikipedia-style document about methylmercury under the categories of environmental pollution and heavy metals. Let me start by understanding the requirements.

First, the structure: H1 for the title, an overview section, several sections with H2 and H3 headings, and maybe references or related documents. The content needs to be accurate, objective, detailed enough, easy to read, and use technical terms with explanations. Also, markdown formatting with proper headings, lists, tables, code blocks if needed, and at least 800 characters.

The title is "메틸수은" (Methylmercury). Let me start by outlining the sections. The overview should introduce what methylmercury is, its sources, and importance. Then maybe a section on chemical properties, sources of pollution, environmental impact, health effects, regulations, and mitigation strategies. Each of these can have sub-sections.

For chemical properties, I need to explain what it is, structure, solubility, etc. Sources could include industrial activities, natural processes, and specific examples like coal-fired power plants or artisanal gold mining. Environmental impact might cover bioaccumulation in the food chain, especially in fish. Health effects would discuss toxicity, how it enters the body, symptoms, and vulnerable populations like pregnant women.

Regulations could mention international agreements like the Minamata Convention, and mitigation strategies like reducing emissions, monitoring, and public education. I should also include a references section with credible sources.

I need to make sure technical terms are explained. For example, "bioaccumulation" might be defined in a sub-section. Also, check for accuracy: methylmercury is an organic compound of mercury, formed by bacteria converting inorganic mercury. It's highly toxic and accumulates in fish, which is why it's a concern.

I should avoid markdown syntax but use the structure as per the user's request. Let me start drafting each section with H2 headings, then H3 for sub-sections. Use bullet points or lists where appropriate. Maybe include a table comparing sources of methylmercury? Or maybe not necessary if it's too detailed. Keep paragraphs concise.

Check that all information is accurate. For example, the Minamata Convention was adopted in 2013, and it aims to reduce mercury emissions. Also, mention how it affects the nervous system, especially in fetuses and children.

Need to ensure the document meets the length requirement. Each section should have enough detail without being too verbose. Maybe add a section on detection methods or case studies? But maybe that's beyond the scope. Focus on key points as per the categories given.

Avoid using code blocks unless there's technical content, which I don't think is necessary here. Use bold for terms when needed but not overdo it. Make sure the language is clear and accessible, even with technical terms explained.