Firm leaders at Pepper Hamilton blamed double-digit declines in revenue and profits last year on a temporary drop in demand in the firm’s health effects practice, and said the financial trend lines are skewed by a particularly strong 2015.

But sources with knowledge of the firm said changes in the health effects litigation practice and a number of lawyer defections had eroded the firm’s performance. Combined with the firm’s failed merger talks with Reed Smith, they said, the situation is driving additional lawyers to leave the firm.