Responses from consumer products companies and battery-makers in response to questions about using graphite in their batteries from polluting plants:

Amazon.com: “We are committed to ensuring the highest standards in all areas of production and manufacturing. We work closely with our suppliers to ensure they meet our standards, and conduct a number of audits every year to ensure our manufacturing partners are in compliance with our policies.”

Apple: An Apple spokesman said that for its current products, the company has switched to synthetic graphite, which is not mined. The company declined to say when it made this change to rely exclusively on synthetic graphite.

General Motors: “GM is committed to transforming the industry by reducing the environmental impact of our vehicles and manufacturing them in the most sustainable manner possible. This transformation includes our global suppliers. We have a process in place to identify sustainability risks in the supply chain which includes economic, environmental and social/governance risks. We require our suppliers to comply with local and regional environmental laws and regulations and to be fair, humane and lawful employers, and to enforce similar requirements from their sub-suppliers.”

LG Chem: “LG Chem is fully aware [that] preemptively corresponding to safety and environment risk is the key element of sustainability. Therefore, LG Chem have established safety and environment policy to share with all employees and out to public. . . . In 2014, LG Chem visited the [graphite] supplier [BTR] in order to inspect the plant management system and a third-party management system, but no specific problems were found. LG Chem shall continuously keep monitoring it.”

LG: “LG Chem has responded to your questions directly.”

Panasonic: “Panasonic has investigated the environmental situation at the mine you cited. We found that the operators received an administrative directive from the local authorities in 2014 and have since that time implemented the necessary environmental countermeasures. Additionally, we learned that the local authorities have approved and confirmed the mine’s completion of those countermeasures.”

Samsung Electronics: “Samsung Electronics is keen to ensure that the subcontractors of its suppliers are committed to comply with our high-level standards and thus mandate all its registered suppliers to complete an annual self-assessment, during which they are required to submit information about the environment, social and health compliance status of their suppliers.

“Samsung is well aware of the corporate world’s responsibilities and roles with problems caused by the mining of minerals. Given the nature of this issue, joint efforts among governments, [nongovernmental organizations] and corporations are urgently needed. As a result, we have pledged to redouble our efforts and find ways to resolve these challenges by listening to greater numbers of stakeholders and actively participating in joint initiatives.”

Samsung SDI (battery maker): “We are currently investigating on your concerns, so at this time we do not have detailed information. Should the investigation raise any red flag, we will be happy to give you an update. Please positively understand it.”

TDK/Amperex Technology Ltd. (ATL): In response to a request for information about the company’s role in the battery supply chain, a spokeswoman for a TDK subsidiary wrote that “TDK and ATL have replied that they would not take this interview as some information may not be disclosed to the publics.”

Toyota: “Toyota does not purchase cobalt and graphite directly; rather, we purchase components that contain these materials from suppliers. However, we make efforts to minimize the impact of our procurement activities on local communities, and we will ask our suppliers to take actions to avoid using certain materials if there is a concern about the source.

“Consistent with our Guiding Principles, we engage suppliers throughout our worldwide operations to help ensure they are aware of and abide by our standards, as well as to assess potential issues. As part of these efforts, we may ask a supplier to make improvements, and we follow up on these improvement activities when necessary.”

Responses from graphite and graphite anode producers in response to complaints of pollution:

BTR: “All subsidiary companies under BTR is environmental friendly and is qualified and approved from the government, and the production is strictly operated according to the related law and regulation.”

Aoyu: A person at Aoyu who answered the phone and identified himself as sales and marketing manager said: “The only thing is the dust, which is black in appearance, so people might think that there is pollution. But in reality, there is no pollution. It’s superficial because it’s carbon. Carbon isn’t harmful — it’s different from coal and cement, because when people breathe coal and cement particles it can cause disease. That doesn’t happen with carbon.”

Haida: Manager Chu Helei sent a garbled message accusing The Washington Post of “espionage.”

Hensen: Deputy General Manager Mo Haibo answered some questions about the company via email but did not respond to questions regarding pollution.