Oil Tanker Spill Statistics 2019 Special edition: 50 years of data


This year's edition of ITOPF’s annual Oil Tanker Spill Statistics publication presents 50 years of data on accidental marine spills of oil from tankers.

ITOPF first began compiling statistics in the mid-1970s in response to the lack of reliable information on the number of oil spills from tankers occurring throughout the world. It was known that oil was being spilt but it had not been established with any accuracy how, when, where, why, or how much. ITOPF, with the owners of almost all the world’s tanker tonnage as its Members, was in a unique position to gather this information. Following an initial pilot exercise, ITOPF’s data collection programme was officially launched in 1974, collating data from 1970. Today, ITOPF continues to gather information from shipping and other specialist publications, as well as from vessel owners, their insurers and ITOPF’s own experience at incidents.

A snapshot of Oil Tanker Spills in 50 years (1970-2019)

Spills are recorded in over a hundred countries, territories and regions around the world.

Map of spills (>7 tonnes) from 1970 to 2019

Major oil spills in history

The largest tanker oil spill in history is the ATLANTIC EMPRESS.

The 20 largest spills that have occurred since the TORREY CANYON in 1967. PRESTIGE, EXXON VALDEZ and HEBEI SPIRIT are included for comparison.

ITOPF Attended 3 in 4 of the major oil spills.

Global Oil Spill Trend

Over the last 50 years, there has been a marked downward trend in oil spills from tankers. The average number of spills per year in the 1970s was about 79 and has now decreased by over 90 percent to a low of 6.

Number of spills (>7 tonnes) from 1970 to 2019

Number of spills

Over 1800 spills have been recorded since 1970. The yearly average recorded for both medium (7–700 tonnes) and large spills (>700 tonnes) this decade is less than a tenth of the average recorded in the 1970s.

Number of medium (7–700 tonnes) and large (>700 tonnes) spills per decade

The lowest annual number of spills was recorded in 2019 and the highest in 1974.

Quantities of oil spilt

Approximately 5.86 million tonnes of oil have been lost as a result of tanker incidents globally since 1970. However, there has been a significant reduction in volume of oil spilt through the decades. The total amount spilt per decade has reduced by about 95% since the 1970s.

A few large spills are responsible for most of the oil spilt annually or in a decade.

Quantities of oil spilt 7 tonnes and over (rounded to nearest thousand)

An interesting pattern of alternating sharp decline and stability can be observed for average volume of oil spilt per decade. Nonetheless, quantity of oil spilt in a particular year or a decade is unpredictable, and trend can be hugely distorted by a single large spill.

Quantities of oil spilt per decade

Causes of spills

The most frequent causes of oil spills are Allisions/Collisions and Groundings.

However, the proportion of Groundings has decreased over the decades, making Allisions/Collisions the current most frequent cause of spills.

Cause of spills per decade

Current trends – the 2010s

When the frequency of spills for this decade alone is reviewed, the usual fluctuations in yearly values within a decade can be seen. As expected, these differences are not as vast as they are for some years in previous decades. As number of spills recorded per year nears zero, the fluctuations are decreasing and the downward trend in yearly average number of spills per decade is likely to slowly stabilise.

The yearly average number of spills for this decade has decreased to a low of 6.2, which marks a 66% drop from last decade’s average.

Number of spills (>7 tonnes) from 2010-2019

Today, about 99.99% of oil transported by sea arrives safely at its destination. The positive reports on trends in oil tanker spills endorse the hard work by governments and industry in improving safety and standards of operations.

* Data relates to spills of 7 tonnes and over from 1970-2019.


Information is gathered from published sources, such as the shipping press and other specialist publications, as well as from vessel owners, their insurers and from ITOPF’s own experience at incidents. While we strive to maintain precise records for all spill information, we cannot guarantee that the information taken from the shipping press and other sources is complete or accurate. The number of incidents, volumes of oil spilt and causes of incidents are based on the most up to date information. From time to time, data is received after publication and, in which case, adjustment to previous records may be made. Consequently, the information provided, should be viewed with an element of caution.

Copyright © ITOPF: All rights reserved 2020