ENOfficial
‘Umar b. al-Khattab said, “Do not wash in water which has been exposed to the sun, for it produces leprosy.” Daraqutni transmitted it.
Source: sunnah.com
Other translations
Arabic
وَعَنْ عُمَرَ بْنِ الْخَطَّابِ رَضِيَ اللَّهُ عَنْهُ قَالَ: لَا تَغْتَسِلُوا بِالْمَاءِ الْمُشَمَّسِ فَإِنَّهُ يُورِثُ البرص. رَوَاهُ الدَّارَقُطْنِيّ
sunnah.com