The widespread use of road salt for winter road maintenance has led to an increase in the salinity of surface water in many seasonally cold areas. Freshwater mussels have a heightened sensitivity to salt, which is a concern, because many Canadian mussel species at risk have ranges limited to southern Ontario, Canada’s most road-dense region. This study examined the effect of winter road runoff on freshwater mussels. The impact of two bridges that span mussel habitat in the Thames River watershed (Ontario, Canada), the second most species-rich watershed for mussels in Canada, were studied. During a winter melt event, bridge runoff, as well as creek surface water surrounding the bridges were collected. Chloride concentrations in samples from bridge deck and tile drains varied (99–8250 mg/L). In general, survival of Lampsilis fasciola glochidia exposed to those samples reflected chloride levels (e.g. 84% at 99 mg/L; 0% at 8250 mg/L), although potassium (60 mg/L) may have at least contributed to toxicity in one sample. Serial dilution exposures with the two most toxic runoff samples revealed 48-h glochidia EC50s of 44% (McGregor Creek Tile Drain) and 26% (Baptiste Creek Deck Drain). During the melt event, the chloride concentrations in creek surface waters downstream of the bridges ranged from 69 to 179 mg Cl⁻/L; effects on glochidia (viability 77–91%) exposed to those waters was minimal. There were no live mussels surrounding one bridge (Baptiste Creek), likely due to poor habitat. At the other targeted bridge (McGregor Creek), fewer mussels were found close (< 100 m up- or downstream) to the bridge than further (> 200 m) away. However, other contributing factors, including agriculture, were present at both study areas.

在冬季道路维护中广泛使用道路盐，导致许多季节性寒冷地区地表水的盐度增加。淡水贻贝对盐的敏感性更高，这是一个令人担忧的问题，因为许多处于危险中的加拿大贻贝物种的活动范围仅限于加拿大道路最密集的安大略省南部地区。本研究考察了冬季道路径流对淡水贻贝的影响。研究了跨越泰晤士河流域（加拿大安大略省）的贻贝栖息地的两座桥梁的影响，这是加拿大第二大贻贝物种丰富的流域。在冬季融化事件期间，收集了桥梁径流以及桥梁周围的小溪地表水。桥面和瓷砖排水管样品中的氯化物浓度各不相同 (99–8250 mg/L)。一般来说，生存Lampsilis fasciola glochidia 暴露于这些样品中反映了氯化物水平（例如，99 毫克/升时为 84%；8250 毫克/升时为 0%），尽管钾（60 毫克/升）可能至少导致了一个样品的毒性。两个毒性最强的径流样品的连续稀释暴露显示 48 小时 glochidia EC50 为 44%（McGregor Creek Tile Drain）和 26%（Baptiste Creek Deck Drain）。在融化事件期间，桥梁下游小溪地表水中的氯化物浓度范围为 69 至 179 mg Cl ^-/L; 对暴露于这些水域的 glochidia（生存力 77-91%）的影响很小。一座桥（巴蒂斯特溪）周围没有活贻贝，可能是由于栖息地恶劣。在另一座目标桥梁（McGregor Creek），靠近桥梁（上游或下游 < 100 m）的贻贝少于远离（> 200 m）的贻贝。然而，两个研究领域都存在其他促成因素，包括农业。