* Sees one-time hit of 300-400 mln euros
* Will adjust year outlook at quarterly results
* Cites overstocking at Brazil pesticides distributors
* Consumer health business still weak (Adds details on industry woes in Brazil, analyst quote)
FRANKFURT, June 30 (Reuters) - Bayer, which is taking over U.S. seeds group Monsanto, said poor sales at crop protection distributors in Brazil and a weaker-than-expected consumer health business would hit earnings by at least 300 million euros ($342 million).
Bayer shares were down 4 percent to 113.45 euros by 1005 GMT after the unscheduled statement.
"At the end of the harvest season in Brazil, regular stock-taking revealed an unexpectedly high channel inventory level of crop protection products," the company said.
The problems in Brazil would result in a one-time hit of 300-400 million euros ($342-$456 million) on full-year earnings before interest, taxes, depreciation and amortisation (EBITDA).
Bayer, currently seeking regulatory approval for its $66 billion takeover of Monsanto, said it would adjust its business outlook when it publishes second quarter results, due on July 27, without providing details.
Bayer has been trying to overcome a weaker than expected performance of key consumer care brands Coppertone sun screen and Dr. Scholl's foot care products, acquired from Merck & Co . It did not specify the impact of that part of the business on earnings.
The agricultural supplies industry has been suffering from three years of weak crop prices, weighing on farmers' demand for seeds and pesticides.
Recession-hit Brazil, a major producer of soybeans, sugarcane and maize and one of the world's largest pesticides market, has been a particular headache with the added burden of tight credit conditions for farmers.
Bernstein analyst Jeremy Redenius said while cuts to 2017 consensus estimates would be relatively small, "the bigger worry is this mis-step in the CropScience business before the integration of Monsanto kicks off."
"Such high inventories should have been recognized and managed sooner. Now we hope they reduce inventories while pricing responsibly," he added. Bernstein rates Bayer as "Outperform".
Bayer earlier this year said a recovery in global demand for crop protection products was likely to be seen first in Asia, eastern Europe and Latin America towards the end of 2017, while markets in North America and Europe would not see a return to more robust growth before 2018.
The company also cited unfavorable currency developments but added its pharmaceuticals division and chemicals business Covestro were still performing strongly, while business at its animal health unit was line with expectations.
When asked about Bayer's plan to file for regulatory approval in Europe for the Monsanto deal this quarter, a spokesman said that remarks by Bayer CEO Werner Baumann last week, reaffirming that goal, were still valid. ($1 = 0.8766 euros) (Reporting by Ludwig Burger; Editing by Mark Potter and Keith Weir)