A science‑based look at the critiques of biochar — and how responsible sourcing and formulation address them.
Biochar has become one of the most discussed soil amendments in modern agriculture — and one of the most misunderstood.
Critics raise concerns about contaminants, carbon permanence, land use, and production variability.
Supporters point to improved soil structure, nutrient efficiency, water retention, and long‑term carbon storage.
Both sides have valid points. And growers deserve to know the real biochar story.
American BioChar Company sits in a unique position in this landscape.
We do not manufacture biochar. Instead, we source high‑quality biochar from a reputable producer who uses controlled pyrolysis and clean feedstocks.
We then craft soil amendments, including charged biochar blends, and also offer uncharged biochar (NAKED Char) for growers who prefer to integrate it into their own systems.
Key Takeaways
- Biochar’s controversies are real — but not universal. Most risks come from poor‑quality production, contaminated feedstocks, or untested materials, not from responsibly sourced, controlled‑process biochar.
- American BioChar Company does not manufacture biochar. We source from a reputable producer using controlled pyrolysis and clean, sustainably harvested Southern Yellow Pine.
- American BioChar Company offers both uncharged and charged products.
- NAKED Char: uncharged biochar (liquid and granular) for growers who want full control.
- Crafted biochar blends: biochar charged with freshwater‑sourced humate for improved nutrient retention and soil performance.
- The science supports biochar’s benefits. Peer‑reviewed reviews show biochar improves soil structure, water retention, nutrient efficiency, and long‑term carbon stability when produced and applied correctly.
- Critiques have scientific grounding — and solutions. Concerns about PAHs, dioxins, carbon permanence, alkalinity, and land use are addressed through clean feedstocks, controlled pyrolysis, testing, and proper application guidance.
- Biochar is not a miracle or a menace. It’s a tool — and its value depends on how it’s made, sourced, blended, and used. American BioChar Company’s role is to ensure growers get the version that works for them in their situation.
This article breaks down the major critiques of biochar and explains what the science actually says.
Contamination Biochar Concerns: PAHs, Dioxins, Heavy Metals
The critique
Poorly controlled pyrolysis or contaminated feedstocks can produce PAHs, dioxins, furans, or heavy metals. These risks are real when biochar is made from waste streams or in uncontrolled kilns.
What the science says
A 2024 review in Frontiers in Soil Science describes biochar as a “sustainable soil conditioner” that improves soil health and crop production when produced from appropriate feedstocks under controlled conditions
A 2024 review in Bioengineering emphasizes that biochar’s environmental impacts — positive or negative — depend on feedstock type, pyrolysis temperature, and production method.
Where American BioChar Company fits
Because we are not the kiln operator, we choose our partners based on:
- Clean feedstock (Southern Yellow Pine)
- Controlled pyrolysis (consistent temperature, low oxygen, engineered systems)
- Testing for contaminants (PAHs, heavy metals, ash content)
We then use this material in both:
- NAKED Char (uncharged biochar, liquid and granular)
- Our crafted biochar blends (charged with freshwater‑sourced humate)
Bottom line: The contamination risks critics cite apply to poorly made biochar — not to the material American BioChar Company sources or sells.
Climate Benefits and the “False Solution” Biochar Debate
The critique
Some argue biochar is oversold as a climate tool. They question carbon permanence and worry that carbon markets may be moving faster than the science.
What the science says
A 2025 review in Discover Soil states that biochar “has gained increasing attention as a sustainable soil amendment.” That is due to its ability to enhance soil health, improve agricultural productivity, and sequester carbon for long periods.
The same review highlights biochar’s role in reducing atmospheric greenhouse gases and supporting climate resilience.
At the same time, researchers note that carbon stability varies by soil type, climate, and management — a nuance critics often point to.
Where American BioChar Company fits
We do not claim biochar is a miracle climate fix.
We do claim:
- The biochar we source has high fixed‑carbon content and stable aromatic structures
- It contributes to long‑term carbon storage
- Its primary value is soil performance, with climate benefits as a co‑benefit
Biochar is not a “false solution.” It’s a soil‑first tool with meaningful carbon advantages when produced and applied responsibly.
Land Use and Resource Diversion for Biochar Production
The critique
If biochar demand grows, biomass will be diverted from food production.
What the science says
Reviews emphasize that biochar is best produced from residues and by‑products, not from primary food crops.
Where American Biochar Company fits
Our biochar supplier uses Southern Yellow Pine, a sustainably harvested forestry product — not food crops or land‑intensive biomass grown specifically for biochar.
Biochar, when sourced responsibly, supports food systems by improving soil health rather than competing with them.
Irreversibility and Soil Chemistry Impact of Biochar
The critique
Biochar is long‑lasting. If you apply the wrong type or too much, you can’t easily remove it. Some biochars are alkaline and may not suit all soils.
What the science says
Biochar’s effects depend on:
- soil pH
- application rate
- biochar type
- cropping system
The Bioengineering review notes that biochar can improve nutrient retention, water holding, and soil structure — but only when matched appropriately to soil conditions.
Where American BioChar Company fits
We offer:
- Uncharged biochar (NAKED Char) for growers who want full control
- Charged biochar blends (with freshwater humate) for growers who want optimized performance
- Application guidance to ensure correct rates and soil compatibility
Irreversibility is exactly why design, testing, and guidance matter.
Production Variability and Energy Footprint of Pyrolysis
The critique
Not all pyrolysis systems are equal. Poorly sealed kilns or inconsistent temperatures can produce ash instead of char or increase contaminants.
What the science says
Reviews consistently highlight that process control determines:
- carbon stability
- porosity
- pH
- contaminant levels
- environmental performance
Where American BioChar Company fits
Because we are not the producer, we can be selective.
We partner only with producers who:
- use engineered, controlled pyrolysis systems
- maintain consistent temperatures and oxygen levels
- test their output for quality and safety
- use sustainable, traceable feedstocks
We then turn that high‑quality biochar into crafted biochar blends; soil amendments designed for predictable performance.
Where Does This Leave Us?
If you only read the critiques, biochar can sound risky, overhyped, or unproven. If you only read the marketing, it can sound like a miracle. The truth, as usual, sits in the middle—and the peer‑reviewed science backs that up.
From recent reviews and research, we can say with confidence that:
- Biochar is a powerful soil amendment that can improve soil structure, water retention, nutrient efficiency, and crop performance when matched correctly to soil and system. https://www.frontiersin.org/journals/soil-science/articles/10.3389/fsoil.2024.1376159/full?utm_
- Biochar is a meaningful carbon tool, capable of storing carbon for long periods and contributing to climate resilience, though its exact impact depends on context and management. https://link.springer.com/article/10.1007/s44378-025-00041-8?utm
- Biochar risks and downsides are real when feedstocks are contaminated, processes are uncontrolled, or products are applied without regard to soil conditions and rates. https://psr.crcjournals.org/biomass-derived-biochar-and-its-role-in-carbon-sequestration-and-soil-health-improvement/?utm_source=copilot.com, https://pubs.rsc.org/en/content/articlelanding/2025/em/d5em00500k?utm_
Biochar’s controversies are real — but they are not universal. They apply to:
- uncontrolled production
- contaminated feedstocks
- untested materials
- uncharged, unblended products
- oversold climate claims
American BioChar Company operates differently:
- We source from a reputable, controlled‑process biochar producer
- We verify quality and safety
- We sell both uncharged biochar (NAKED Char) and charged blends
- We use freshwater‑sourced humate to enhance nutrient retention and pH buffering
- We design products for soil performance, not carbon hype
- We support growers with guidance, not guesswork
- Our products are OMRI-listed and IBI-certified
Biochar is not a myth, and it’s not a miracle. It’s a tool. Used carelessly, it can disappoint or cause problems. Used well, it can transform how soil holds water, nutrients, and carbon—and support more resilient, efficient, and productive systems for the long term.
That’s the version of biochar we stand behind. And that’s the conversation we’re committed to having—openly, with the science on the table.
Contact us; we love to talk about biochar and our biochar blends. You’re probably interested in what other people have to say about our biochar products. Here is a link to our results and testimonials. Hear what our customers have to say.
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