Just under half of U.S. investors have a problem with bitcoin’s environmental issues, with some of them apparently swayed by Tesla CEO Elon Musk’s tweets on the matter, a new survey shows.

Some 49% of 1,103 respondents to the Investing.com survey said that “bitcoin being environmentally unfriendly" is an issue for them as an investor, according to a summary of the results posted on the information service’s website. 

The survey provides some evidence of how drastically some investors’ opinions on bitcoin changed after  Musk tweeted his concerns in May, when he reversed an earlier policy of accepting the cryptocurrency as payment for Tesla's electric vehicles.

Since then, there’s been about a 40%% price drop for the world’s largest cryptocurrency, according to the CoinDesk Bitcoin Price Index. Cathie Wood, CEO of Ark Investments, said at the Robin Hood Investors Conference on June 16 that the downturn was due to investors’ growing awareness of the sheer amount of electricity it takes to mine the cryptocurrency. 

Some 70% of investors who took part in Investing.com’s survey said they would favor a more “green” cryptocurrency, while 36% didn’t even realize that bitcoin had environmental implications before Musk’s comments on the issue. 

According to Investing.com, 30% of the respondents sold their bitcoin last month, with one in five attributing the decision to Musk’s comments about the environment. 

Musk’s tweets on cryptocurrency were seen as “annoying” by 33% of respondents, “unfair” by 22% and “entertaining” by 27%, the summary reads. 

“After being hailed and crowned as king of the crypto community, Elon Musk has made himself some new enemies lately, following his recent shock about-face on bitcoin,” said Jesse Cohen, an analyst at Investing.com. “For an asset whose price is driven mostly by psychological sentiment and momentum, bitcoin could have a hard time recovering.”

When respondents were asked if Musk’s “manipulation of cryptocurrency values has changed their view of that investment,” 51% said Musk has “too much power” and 24% said they don’t believe the billionaire has too much influence.