Look at the loan terms, it'll freak you out more than the term "toxic". Junkhustler has done a good job posting these terms, which again, are in the SEC filings. I'm not going to dig them up for you. Maybe if junkhustler is feeling nice he'll do so for you.
The lower the share price the more shares that are needed to repay the debt IF the company can not repay the loan back with cash and interest.
The more shares issued to pay the debt causes the share price to fall requiring yet more share needed to repay the same amount of debt, as this cycle continues share price continues to fall leading to the term death spiral, as share price dwindle towards zero.
From Larry past history, and considering the actually amount of money owed Mantra is far from this occurring in the near future.