First, an enzyme called ADH turns alcohol into acetaldehyde, which is toxic.

首先，乙醇脱氢酶 (ADH) 将酒转化为有毒的乙醛。

Also, oral bacteria convert ethanol to acetaldehyde which is a carcinogen.

此外，口腔微生物群可将乙醇转化为致癌物——乙醛。

Alcohol breaks down in the body into a substance called acetaldehyde.

酒在体为一种叫做乙醛的物质。

The acetaldehyde then gets converted to acetate and goes into the mitochondria like last time.

乙醛之后再被转换为乙酸盐并和之前一样，进线粒体。

Then, an enzyme called ALDH converts the toxic acetaldehyde to non-toxic acetate.

接着，乙醛脱氢酶(ALDH) 将有毒的乙醛转化为无毒的醋酸盐。

The body has an enzyme that breaks down acetaldehyde.

体有一种乙醛的酶。

A hangover is suspected to be the result of alcohol being metabolized into acetaldehyde.

酒醉就是由酒的代谢产物——乙醛造成的。

Ethanol doesn't need insulin to get into the cell, it just diffuses in there and is converted to acetaldehyde.

乙醇不需要胰岛素进细胞，它直接融进去肝细胞里面（酒又融水又融油，细胞壁挡不住它）被转化成乙醛。

If acetaldehyde sounds familiar that maybe because it's similar to formaldehyde. It's toxic. That's why it triggers the immune responds.

你可能觉得乙醇似曾相识，那是因为他和甲醛一样，有毒。这就是为什么我们的免疫系统会产生反应。

And the second quickly turns acetaldehyde into acetate, which is similar to vinegar and easy for the body to eliminate.

而第二种酶此时会快速地将乙醛变成乙酸酯。乙酸酯的功能和醋很相似，可以轻易地从体排出。

First, enzymes convert the alcohol to acetaldehyde, a substance that can damage cells over time.

首先，酶将酒转化为乙醛，乙醛是一种会随着时间的推移损害细胞的物质。

These enzymes break down alcohol and convert it into something called acetaldehyde.

这些酶酒并将其转化为乙醛。

Acetaldehyde is poison. It will kill cells.

乙醛是毒药。它会杀死细胞。

But acetaldehyde is quickly converted into acetate, a much more stable intermediate, before it breaks down into carbon dioxide and water.

但是乙醛在成二氧化碳和水之前会迅速转化为醋酸盐，这是一种更稳定的中间体。

Unfortunately, ethanol and toxic alcohol metabolites like acetaldehyde also pass freely through the placenta, but the fetal liver doesn't have the necessary enzymes to metabolize them, so they build up inside the fetus really fast.

不幸的是，乙醇及有毒的酒代谢产物，如乙醛，也可自由通过胎盘，而胎儿的肝脏却没有这些物质所必需的酶，因此它们可以在胎儿体快速积聚。