Unsubstituted and methylated polycyclic aromatic hydrocarbons (22 PAHs and 17 Me-PAHs) were examined in surface sediments collected from the Red River and four inner-city rivers of Hanoi City, Vietnam. Concentrations of total PAHs and Me-PAHs ranged from 52 to 920 (median 710) and from 70 to 2600 (median 1000) ng/g dry weight in samples of dry and wet seasons, respectively. Significant correlation was observed between total PAHs and organic carbon contents (Spearman's ρ = 0.782; p < 0.05). PAHs were more abundant than Me-PAHs in all samples and dominated by 4–6 ring compounds. The most predominant PAHs were benzo[ghi]perylene, benzo[b/j]fluoranthene, chrysene, pyrene, fluoranthene, and phenanthrene. Methylated derivatives of naphthalene, phenanthrene, anthracene, and benz[a]anthracene were frequently detected. The patterns of PAHs indicated principal pyrogenic sources (notably gasoline exhaust) in this highly urbanized area. The occurrence of several PAHs were occasionally associated with adverse effects on benthic organisms of the inner-city rivers.

在从红河和越南河内市的四条内城河流收集的表层沉积物中检测了未取代和甲基化的多环芳烃（22 种 PAH 和 17 种 Me-PAH）。在旱季和雨季的样品中，总 PAH 和 Me-PAH 的浓度范围分别为 52 至 920（中位数 710）和 70 至 2600（中位数 1000）ng/g 干重。在总多环芳烃和有机碳含量之间观察到显着相关性（Spearman's ρ  = 0.782；p  < 0.05）。在所有样品中，PAHs 比 Me-PAHs 更丰富，并且以 4-6 环化合物为主。最主要的多环芳烃是苯并[ ghi ]苝、苯并[ b/j]荧蒽、芘、芘、荧蒽和菲。经常检测到萘、菲、蒽和苯并[ a ]蒽的甲基化衍生物。PAHs 的模式表明了这个高度城市化地区的主要热源（特别是汽油尾气）。几种多环芳烃的出现偶尔会对内城河流的底栖生物产生不利影响。