Portfolio Update

BLACKROCK COMMODITIES INCOME INVESTMENT TRUST PLC

All information is at 31 August 2009 and unaudited.

Performance at month end with net income reinvested

                         One    Three       Six       One     Since    
                       Month   Months    Months      Year    Launch*  
                                                                               
Net asset value         5.6%     6.9%     41.1%    -20.8%     32.4%             
Share price             0.0%     4.5%     34.7%    -18.8%     27.1%             

Sources: Datastream, BlackRock
* 13 December 2005

At month end                                                                   
                                                                               
Net asset value - capital only:                    109.72p                     
Net asset value - cum income**:                    111.21p                     
Share price:                                       108.75p                     
Discount to NAV (capital only):                      0.88%                     
Net yield:                                           5.03%                     
Gearing - cum income:                                4.38%                     
Revenue per share:                                   1.49p^                    
Total assets:                                      £85.48m^^                   
Ordinary shares in issue:                       74,825,662                     

**Includes net revenue of 1.49p.
^Revenue per share is stated after deduction of the first quarterly dividend of
1.35p which was paid on 24 April 2009 and the second quarterly
dividend of 1.35p which was paid on 24 July 2009.
^^includes current year revenue.

                                    % of Total                          % of Total
Sector Analysis                         Assets    Country Analysis          Assets
                                                                               
Integrated Oil                            22.3    Europe                      28.1
Diversified                               20.0    USA                         22.3
Exploration & Production                  14.8    Canada                      14.7
Copper                                     6.1    Asia                        11.1
Oil Services                               5.3    Latin America                9.3
Gold                                       5.2    South Africa                 6.5
Iron Ore                                   4.1    China                        1.8
Coal                                       4.0    India                        1.7
Fertilisers                                3.7    Australia                    1.2
Aluminium                                  3.4    Africa                       0.8
Nickel                                     2.5    Russia                       0.7
Platinum                                   2.4    Current assets               1.8
Tin                                        1.7                               -----
Zinc                                       1.5                               100.0
Distribution                               1.2                               =====
Current assets                             1.8                                 
                                         -----                                 
                                         100.0                                 
                                         =====                                 

Ten Largest Equity Investments (in alphabetical order)                         
                                                                               
Company                                   Region of Risk                       
                                                                               
Anadarko Petroleum                        USA                                  
BHP Billiton                              Global                               
BP                                        Global                               
Exxon Mobil                               Global                               
Freeport McMoRan Copper & Gold            Asia                                 
Kumba Iron Ore                            South Africa                         
Rio Tinto                                 Global                               
StatoilHydro                              Europe                               
Total                                     Global                               
Vale                                      Latin America                        

Commenting on the markets, Richard Davis, representing the Investment Manager
noted:

Base metals made further gains in August, led by copper and nickel which closed
the month up 12.9% and 11.1% (in US Dollar terms) respectively, reflecting the
better than expected industrial production and power demand data from Europe.
These data, however, contrasted with signs of slowing imports into China.
July's trade data from China indicated that copper, aluminium, zinc and lead
imports all declined during the month, albeit from record levels in June.
Mining shares gained 1.0% (in Sterling terms) in August. The key news story in
the precious metals market was the announcement by the European Central Bank
that a new five-year Central Bank Gold Agreement has been signed to replace the
existing agreement that expires at the end of September. Importantly, the quota
has been reduced from 2,500 tonnes to 2,000 tonnes for the period. Gold sales
under the existing agreement have to date totalled only 1,867 tonnes, around
25% below the 2,500-tonne quota. The new agreement will also incorporate the
sale of 403 tones of gold by the IMF. Gold prices closed the month up US$14/oz
at US$948/oz.

In the energy market, oil prices were largely unchanged in August, closing at
$70/bbl while natural gas fell back to just US$2.24/MMBTU, close to half its
price at the beginning of 2009. The latest International Energy Agency oil
market report provided some support for investors as they upgraded 2009 and
2010 oil demand forecasts. The new forecast, which was primarily driven by a
more constructive outlook for Asia, upgraded demand in 2009 and 2010 by 190kb/d
and 70kb/d respectively. The spot price for natural gas continued its decline
in August as supply beat expectations despite severe cuts to drilling activity.
The amount of natural gas in storage is reaching the total available capacity,
which may lead to further near-term pricing pressure. However, gas futures are
trading at higher levels reflecting the long term marginal cost of supply.
Natural gas for delivery at Henry Hub in two years time is currently trading at
over US$6/MMBTU. Energy shares gained 3.2% (in sterling terms).

In company news, BP announced a significant oil discovery in the Gulf of
Mexico. The discovery at the Tiber Prospect is thought to contain around 3
billion barrels of oil and is located at a depth of over 10 km below sea level.
The announcement of this find may enable BP to boost their output from the Gulf
of Mexico by around 50% to 600,000 barrels of oil equivalent after 2020.
However, this discovery also re-opened the debate about the future of oil
supply, with many analysts pointing out that the field will take many years to
come online, faces significant development challenges and that existing fields
are declining faster than expected.

Latest information is available by typing www.blackrock.co.uk/its on the
internet, "BLRKINDEX" on Reuters, "BLRK" on Bloomberg or "8800" on Topic 3 (ICV
terminal).

25 August 2009