| POS | BIB | ATHLETE | COUNTRY | MARK | Reaction Time | 
|---|---|---|---|---|---|
| 1 | USA | United States Junior |  USA | 43.95 Q WJL | 0.179 | 
| 2 | NED | Netherlands Junior |  NED | 44.68 Q SB | 0.175 | 
| AUS | Australia Junior |  AUS | DQ | 0.168 | |
| BAH | Bahamas Junior |  BAH | DNF | 0.180 | |
| SLO | Slovenia Junior |  SLO | DNF | 0.144 | |
| CHN | PR of China Junior |  CHN | DNS | 0.000 | 
| POS | BIB | ATHLETE | COUNTRY | MARK | Reaction Time | 
|---|---|---|---|---|---|
| 1 | GBR | Great Britain & N.I. Junior |  GBR | 44.47 Q SB | 0.179 | 
| 2 | BRA | Brazil Junior |  BRA | 44.79 Q SB | 0.201 | 
| 3 | BEL | Belgium Junior |  BEL | 44.88 q NJ | 0.228 | 
| ESP | Spain Junior |  ESP | DQ | 0.172 | |
| CAN | Canada Junior |  CAN | DQ | 0.153 | |
| JAM | Jamaica Junior |  JAM | DNF | 0.191 | 
| POS | BIB | ATHLETE | COUNTRY | MARK | Reaction Time | 
|---|---|---|---|---|---|
| 1 | GER | Germany Junior |  GER | 44.27 Q SB | 0.169 | 
| 2 | NGR | Nigeria Junior |  NGR | 44.58 Q SB | 0.155 | 
| 3 | POL | Poland Junior |  POL | 45.02 q SB | 0.218 | 
| 4 | ITA | Italy Junior |  ITA | 45.15 SB | 0.160 | 
| 5 | SUI | Switzerland Junior |  SUI | 45.61 | 0.153 | 
| RSA | South Africa Junior |  RSA | DQ | 0.188 |