Is the word impacto the same in Brazilian and European Portuguese?

Yes

The meaning, spelling, and grammatical usage of "impacto" are identical in both Brazilian and Continental Portuguese. The only difference lies in pronunciation.

In Brazilian Portuguese, the vowels are typically more open and clearly articulated, and the rhythm of speech is more "syllable-timed" (each syllable receives a more even amount of time). In Continental Portuguese, vowels are much more closed and often reduced or almost eliminated in unstressed positions (a "stress-timed" rhythm), which can make the word sound shorter or more clipped to a Brazilian ear.

Brazilian Portuguese Examples

1. O impacto da batida foi muito forte. (The impact of the crash was very strong.)
2. A nova lei vai causar um grande impacto na educação. (The new law will cause a great impact on education.)
3. Esse projeto tem um impacto social muito positivo. (This project has a very positive social impact.)
4. O impacto da notícia assustou todo mundo. (The impact of the news scared everyone.)
5. Precisamos avaliar o impacto ambiental dessa obra. (We need to evaluate the environmental impact of this construction.)

Continental Portuguese Examples

1. O impacto da colisão foi muito forte. (The impact of the collision was very strong.)
2. A alteração vai causar um grande impacto na educação. (The change will cause a great impact on education.)
3. Este projeto tem um impacto social muito positivo. (This project has a very positive social impact.)
4. As consequências da notícia foram imediatas. (The consequences of the news were immediate.)
5. É necessário avaliar o impacto ambiental desta obra. (It is necessary to evaluate the environmental impact of this work.)