# Assessing Fatality Risks in Maritime Accidents: The Influence of Key Contributing Factors
## 3 Problem Background
### Alcohol Content and Its Effects  
Blood alcohol content (BAC) represents the concentration of alcohol in the blood, measured as \"weight by volume\". BAC can be measured as milligrams of ethanol per millilitre of blood (mg/mL), which is equivalent to grams per litre (g/L). Sometimes, BAC can be measured as percentage by volume. For example, 0.05 g/100 mL = 0.05% = 0.5 mg/mL = 0.5 g/L. On the other hand, breath alcohol concentration (BrAC) represents the concentration of alcohol in the breath. For the purposes of this paper, while investigating the alcohol content of seafarers on board maritime vessels, BAC was selected as the primary variable. Consequently, it was necessary to convert BrAC to BAC for consistency. BrAC measurements are typically reported in investigation reports where the individuals involved were alive, while BAC values are obtained from deceased seafarers. Alcohol inhibits the central nervous system, and as the blood alcohol concentration (BAC) increases, its effects intensify, leading to various physical and mental changes. The metabolization of alcohol varies based on individual body constitution, consumption circumstances (including food and drink intake), and daily physical condition changes. Drunkenness is an acute intoxication symptom caused by alcohol ingestion, affecting the central nervous system. This intoxication results in ataxia (e.g., staggering and slurring), autonomic symptoms (e.g., facial flushing and sweating), and a general decline in central nervous system functions (e.g., impaired attention and judgment). As BAC increases, significant consciousness disturbances occur [19]. Table 1 outlines the amounts of alcohol consumed, BAC levels, and states of general intoxication. \begin{table}
\begin{tabular}{l l} \hline \hline
**Stage (BAC \%)** & **State of Intoxication** \\ \hline \multirow{2}{*}{Euphoria (0.02–0.05)} & feeling of invigoration, reddening skin, cheerfulness, minor impairment of judgment and coordination \\ \hline \multirow{3}{*}{Slight intoxication (0.05–0.10)} & slight tipsiness, active hand movements, without inhibition, higher body temperature/rapid heartbeat, increased impairment of judgment, memory \\  & and coordination \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Amounts of alcohol consumed (BAC) and its effects. While the fundamental process of metabolizing alcohol is the same for everyone, genetic, biological, and environmental factors can influence how quickly this process occurs. Factors influencing the metabolization of alcohol differ, from genetic differences to environmental and cultural factors:  
* Genetic differences--These are the primary enzymes responsible for metabolizing alcohol--alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH). Genetic variations in these enzymes can affect how quickly alcohol is metabolized [5]. * Cultural and environmental factors--cultural norms on drinking can influence tolerance and the adaptation of the body to alcohol. Populations may have developed a higher tolerance for alcohol during the years of consumption. * Diet and lifestyle can also impact how alcohol is processed, based on different types of diets [25]. * Body composition--generally, individuals with more body mass have a lower BAC after consuming the same amount of alcohol than those with less body mass [26]. * Gender--the effects of alcohol consumption differ significantly between men and women, largely due to biological and metabolic variations. For instance, women tend to reach higher blood alcohol concentrations (BAC) than men after consuming the same amount of alcohol, due to lower body water content and hormonal differences. Additionally, women may experience more severe alcohol-related health consequences, such as liver damage, at lower consumption levels [27]. * Regular consumption--people who consume alcohol regularly may develop a higher tolerance; so, they may have lower BAC levels than occasional drinkers after consuming the same amount of alcohol [19].